Atlas of Common Skin Diseases In Australia

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COMMON SKIN DISEASES I

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Robin Marks Anne Plunkett Kate Merlin Nicole Jenner Department of Dermatology St Vincent’s Hospital, Melbourne

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Published by the Department of Dermatology, St Vincent’s Hospital, Melbourne, Victoria Parade, Fitzroy, Victoria 3065 Australia. Telephone +61 3 9288 3293 Fax +61 3 9288 3292 © Department of Dermatology, St Vincent’s Hospital, 1999 No part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted in any form or by any means without the prior written permission of the copyright owner.

ISBN 1–875271–31–7

Foreword Professor Robin Marks and the Department of Dermatology at St Vincent’s Hospital in Melbourne are to be congratulated on producing this Atlas of Common Skin Diseases in Australia. Due to their fine efforts, we now have a clear idea of the prevalence and morbidity of common skin conditions in this country. Despite the significant prevalence of skin disease in Australia, as illustrated in this Atlas, this important healthcare issue has been given low priority in the community. Consequently and disappointingly, dermatology has received insufficient Government attention and inadequate funding for provision of clinical services, research and training. A key function of the Australasian College of Dermatologists is education. Through its range of educational activities, information concerning common skin conditions is circulated regularly amongst medical students, general practitioners, other medical practitioners and allied interest groups. This unique Atlas provides us with further important information and it should become an essential source of reference for anyone interested in Australian dermatology. Medical and allied health trainees, and others interested in ensuring the resources required for maintaining an appropriate profile and high standard of dermatological healthcare in Australia, would find the Atlas particularly valuable. The College is very pleased indeed to be associated with the launch of this Atlas and we wish it every success.

DUDLEY HILL President

STEPHEN LEE Honorary Secretary

THE AUSTRALASIAN COLLEGE OF DERMATOLOGISTS

—— Foreword ——

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—— Atlas Of Common Skin Diseases ——

Introduction Skin diseases are a bit like the common cold. Apart from some of the skin cancers, they are not recorded in any official registry. They vary enormously from mild conditions which may affect only the appearance of the skin to severe diseases which are totally incapacitating. The degree of treatment required, or even sought, varies accordingly. Nevertheless, every medical practitioner knows that there are plenty of people suffering with these conditions. A comprehensive survey of general practitioners’ workloads in Australia revealed that skin problems were the primary reason for at least 15% of consultations. On the other hand, community-based data collections show that medical practitioners are consulted about skin conditions by less than 50% of those who have them. People frequently seek advice from others in the community including pharmacists, family or friends and naturopaths, or they merely prescribe for themselves based on information from elsewhere.

This Atlas is only the beginning. It is not enough just to record that there are problems. The next step is to do something about them.

Like the common cold, everyone knows skin conditions are a problem, but until major community-based surveys are undertaken, no one realises the frequency and degree to which people suffer. In 1995, a new academic Department of Dermatology was formed at St Vincent’s Hospital in association with the University of Melbourne, the Australasian College of Dermatologists and the Skin and Cancer Foundation of Victoria. It was decided that the direction of research should be into the frequency and morbidity of common skin conditions in the community. After all, these conditions are the basis for the vast majority of dermatologists’ work. Their work includes not only providing care for patients with skin disease, but also teaching other medical professionals the approach to and management of these conditions.

This Atlas is a summary of the data that have been gathered over the last five years. Skin cancers are not included as they have been well reported elsewhere. The data presented here are startling. However, they do confirm an impression that most health professionals develop after some years of contact with the public. They show clearly that skin diseases are common, they cause considerable morbidity in the community, and people with them require better care. This Atlas is only the beginning. It is not enough just to record that there are problems. The next step is to do something about them. We now have data demonstrating quite clearly where there are problems and we look forward to using these data as the basis for taking steps to relieve them in the future.

Robin Marks Professor of Dermatology St Vincent’s Hospital, Melbourne November 1999

—— Introduction ——

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—— Atlas Of Common Skin Diseases ——

Contents

Methods..............................................................2 What Skin Diseases Do People Say They Have? .............................................4 What Skin Diseases Do People Really Have? Acne ..............................................................6 Nappy Rash (Napkin Dermatitis) ..................10 Atopic Dermatitis (Eczema) ..........................12 Seborrhoeic Dermatitis ................................16 Psoriasis ......................................................18 Warts...........................................................20 Tinea Pedis and Tinea Unguium ..................24 Birthmarks...................................................26 Campbell de Morgan Spots .........................29 Seborrhoeic Keratoses.................................30 Where Do People Seek Advice For Treatment Of Common Skin Diseases? ........................32 Recommendations ............................................36 Acknowledgements ...........................................39

—— Contents ——

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Methods The data presented in this Atlas are a compilation of a number of different studies undertaken by the Department of Dermatology over the last five years. They have been divided into different components and are presented as:- what skin diseases do people say they have when they are asked; what skin diseases do people really have when they are examined by dermatologists; the severity of the skin diseases that have been found on examination; where do people seek advice for treatment of common skin diseases; and is the treatment that people are currently using likely to be effective. The terms skin conditions and skin diseases are used, almost interchangeably at times, throughout the Atlas. This allows us to include conditions like Campbell de Morgan spots or some of the birthmarks which would not normally be classified as disease. Community-based surveys should be carefully designed to sample people who are representative of the whole population. Such surveys depend upon the ability to make contact with representative samples of people of all ages from birth to death. They seek self-report information on the presence of the skin diseases, the treatment and where they have received it. Respondents are then examined by a person experienced in skin disease, i.e. a dermatologist, to reveal whether or not they have a skin condition and what it is. There is no simple method of sampling the whole community at all ages in Australia. For that reason, the population-based surveys represented here have been performed in different ways. They vary according to the age groups of the people being surveyed and the ability to reach those people within age strata in a way which ensures that they are representative of the Australian population. They also vary according to what information is being sought. The data for the chapter on “what skin diseases do people say they have?” come from a communitybased telephone survey in which 416 people were asked if they suffered from skin disease and where they were seeking advice. These are self-reports of skin disease for which we have no clinical examination to confirm the diagnosis. The data for the section “what skin diseases do people really have?” where our dermatologists have examined people to determine the true frequency of skin disease in the community comprise three different studies. The first study “The Tiny Tots

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Survey” included 1,116 children aged from birth to 5 years. The children were examined from a random selection of kindergartens, child care centres and Maternal and Child Health Centres in urban and rural Victoria. In this survey the specific conditions sought in detail included napkin dermatitis (nappy rash), seborrhoeic dermatitis (cradle cap), birth marks, including haemangiomas and melanocytic naevi, and atopic eczema (dermatitis). The second survey “The School Skin Survey” was a school-based study of 2,491 children aged from 4-18 years. The schools were randomly selected from Government, Catholic and Independent schools in both urban and rural Victoria. In this survey, the specific conditions sought in detail included acne, warts, tinea pedis and atopic eczema. Although other conditions, including psoriasis and seborrhoeic dermatitis were recorded, the numbers and information are insufficient to be confident of the true prevalence in this age group. Therefore, they are not reported in this Atlas. The final community-based survey “The Maryborough Skin Health Survey” was of 1,457 adults aged 20 years and over who were randomly selected from the population of Maryborough in Central Victoria. In this survey specific conditions sought in detail included acne, warts, tinea pedis and tinea of the nail (unguium), psoriasis, atopic eczema, seborrhoeic keratosis and Campbell de Morgan spots (punctate haemangiomas). Although skin cancer was recorded, it is not reported here as that has been well covered in other publications. Each of the surveys required voluntary informed consent from the participants or their parents once the randomisation of who would be offered an examination was completed. The final chapter on “where do people seek advice for treatment of common skin diseases?” involved two pharmacy-based surveys in Maryborough seeking information from people who bought skinrelated products. It included information obtained in the three community-based skin examination surveys and the telephone survey of self-report data mentioned above. It can be seen that there are different methods used in each of the surveys that are being reported here and different methods of population sampling. Technically speaking, it is not possible to put them all together and come up with single curves derived from different studies. For that reason, the

—— Atlas Of Common Skin Diseases ——

frequency data are presented in three categories according to the age of the participants and the survey in which data were gathered. On several occasions, we have put the data from the three surveys together to give easy scanning, bearing in mind that they are not strictly compatible. Severity of the conditions was divided into minimal, mild, moderate and severe. These are clinical categories based on a classification of minimal: only a small area affected which may not even have been noticed by the person or their carer; mild: a small area affected, which responds to simple treatment available from a pharmacist, or very mild treatment from a medical practitioner; moderate: more widespread disease that would require treatment from a general practitioner with the use of medications available on prescription only; and severe: widespread active involvement which would require specialist advice. One of the other ways of determining the effect of these diseases, rather than just describing the severity, is to seek the morbidity associated with them. The morbidity is measured in regard to the direct and indirect effects of a skin disease on the individual’s work, home and social life. A Dermatology Life Quality Index (DLQI) has been used to include questions about the effect of these diseases in various aspects of a person’s life. These questions include symptoms related to the disease directly; whether or not it created embarrassment or interfered with such things as shopping or social activities; what effect it has had on relationships with other people; whether work or studying has been affected; and how much of a problem has been created by the treatment that has been necessary. The DLQI was used predominantly in the Adult Survey with some use in the School Survey. DLQI scores are reported in the Atlas where they are available, giving the responses categorised from “affected very much” to “not being affected at all” in each of the categories of the questionnaire. Full descriptions of the exact method for each of the surveys reported in this Atlas are given in the references at the end of this section. Further reading from this list is recommended for those who would like more detailed information on the epidemiological methods involved.

REFERENCES 1. The prevalence and morbidity of common skin diseases among adults in Maryborough, Victoria: The Maryborough Skin Health Survey; 1997-1998. Final Report. Dept of Dermatology, St Vincent’s Hospital, Melbourne. 2. The prevalence and morbidity of common skin diseases in Victorian school children. The School Skin Survey, 1996-1997. Final Report. Dept of Dermatology, St Vincent’s Hospital, Melbourne. 3. The prevalence and morbidity of common skin diseases amongst infants and preschool children. The Tiny Tots Survey, 1998-1999. Final Report. Dept of Dermatology, St Vincent’s Hospital, Melbourne. 4. Gill D, Merlin K, Plunkett A, Jolley D, Marks R. Population based surveys on the frequency of common skin diseases in adults - Is there a risk of response bias? Clin Exp Dermatol. 1999 (In Press). 5. Kilkenny M, Merlin K, Plunkett A, Marks R. The prevalence of common skin conditions in Australian school students: 3. Acne vulgaris. Brit J Dermatol. 1998; 139:840-845. 6. Kilkenny M, Merlin K, Young R, Marks R. The prevalence of common skin conditions in Australian school students: 1. Common, plane & plantar viral warts. Brit J Dermatol. 1998; 138:840-845. 7. Kilkenny M, Stathakis V, Jolley D, Marks R. Maryborough Skin Health Survey: Prevalence and sources of advice for skin conditions. Australas J Dermatol. 1998; 39:233-237. 8. Kilkenny M, Yeatman JM, Stewart K, Marks R. The role of pharmacists and general practitioners in the management of dermatological conditions. Int J Pharmacy Practice. 1997; 5:1115. 9. Mar A, Tam M, Jolley D, Marks R. The cumulative incidence of atopic dermatitis in the first 12 months amongst Chinese, Vietnamese and Caucasian infants born in Melbourne, Australia. J Am Acad Dermatol. 1999; 40:597-602. 10. Marks R, Kilkenny M, Plunkett A, Merlin K. The prevalence of common skin conditions in Australian school children: 2. Atopic Dermatitis. Brit J Dermatol. 1999; 140:468-473. 11. Merlin K, Kilkenny M, Plunkett A, Marks R. The prevalence of common skin conditions in Australian school students: 4. Tinea Pedis. Brit J Dermatol. 1999; 140:897-901. 12. Plunkett A, Merlin K, Gill D, Zuo Y, Jolley D, Marks R. The frequency of common non-malignant skin conditions in adults in central Victoria, Australia. Int J Dermatol. 1999 (In Press). 13. Yeatman JM, Kilkenny MF, Marks R. The prevalence of seborrhoeic keratoses in an Australian population: Does sunlight play a part in their frequency? Brit J Dermatol. 1997; 137:411-414. 14. Yeatman J, Kilkenny M, Stewart K, Marks R. Advice about management of skin conditions in the community: Who are the providers? Australas J Dermatol. 1996; 37 Suppl 1 S46-S47.

—— Methods ——

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What Skin Diseases Do People Say They Have? Everyone in the community will suffer from at least one skin condition during their lifetime. Conditions such as warts and acne are almost universal at certain ages. However, whether people recognise or report many of these common conditions as disease will vary according to the area affected and the severity of the problem. Memory for minor problems fades very rapidly so that recall of past skin conditions may be fraught with under-reporting. The nature of the questions seeking information on whether people have skin disease determines the frequency of response. Some conditions are more common or active at certain times of the year than others. Thus a questionnaire undertaken in winter may reveal a higher prevalence of dermatitis/eczema or acne than a questionnaire seeking the frequency of these conditions undertaken in summer. On the other hand, tinea of the feet (athlete’s foot) and skin cancer are often more frequently reported in the summer months than in the winter months. Thus what skin diseases people say they have may not necessarily be a true picture of what is really occurring in the community. The Australian Government through the Australian Bureau of Statistics undertakes national health surveys on a regular basis. In these surveys, relatively broad questions are used to determine the frequency of self-reported disease. In the 1989/90 survey, 12.7% of the population reported that they

had a disease of skin and subcutaneous tissue within the past two weeks. These are open-ended questions without prompting for specific diagnoses. People are more likely to remember a condition, particularly if it is not symptomatic, only when they are prompted specifically on whether or not they have had it. For example, a person when asked do they have skin disease may say no, even though they may have a wart on their finger. However, when asked specifically do they have a wart on their finger or elsewhere, they may then answer yes. We undertook a computer-assisted telephone interview survey in the city of Maryborough in which 416 adults agreed to answer questions not only on whether or not they had had skin disease recently, but also more specifically on what were the conditions (including prompting questions) that they had. The interviews took approximately 5-10 minutes to complete and were undertaken in midwinter in the months of July and August. Twenty seven percent of people reported having one or more skin conditions over the previous two weeks, with 25% of those reporting that they had more than one skin condition. There were slightly more women (51.4%) than men (48.6%) in the group who reported having a skin condition. Of those who had sought treatment for their problem, 65% reported that the condition was mild, 24% reported moderate and 13% reported that the condition was severe.

Table 1 — Prevalence of self reported skin diseases in adults Prevalence % (95% confidence interval) Past 2 weeks Acne/pimples Cold sores Dermatitis/eczema Psoriasis Skin cancer Thrush Tinea Urticaria/hives Warts

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16.2 15.1 25.5 4.5 0.5 2.5 11.2 1.1 16.1

(9.6-22.7) (7.3-18.9) (18.1-32.8) (1.0-7.9) (0.0-0.9) (0.2-4.8) (5.9-16.5) (0.0-2.7) (9.8-22-4)

Past 6 months (excluding last 2 weeks) 9.4 30.3 12.6 3.5 5.0 5.7 19.4 0.9 8.6

—— Atlas Of Common Skin Diseases ——

(5.4-12.5) (23.9-56.7) (7.9-17.3) (0.9-5.1) (2.3-7.7) (2.7-8.6) (15.8-24.9) (0.0-2.1) (4.9-12.4)

When asked about the past six months, 59% of people reported having at least one skin condition. Treatment was used for the majority of these conditions with the exception of acne and warts. Almost 70% of acne and 70% of warts were not treated by those people who said they had them. The majority of skin conditions reported within the last six months were regarded as mild (74%) with 18% considered by respondents to be moderate and the remaining 8% were classified as severe. A breakdown of the prevalence of the conditions reported by these adults (18 years and over) is shown in Table 1. As predicted, they show that the seasonal related conditions acne and dermatitis were more common at the time (winter) but less common in the last 12 months (including summer). The figures for tinea, skin cancer and cold sores are the other way around. In telephone surveys of this nature, the diagnosis suggested by the respondent is unable to be confirmed by clinical examination. In the Tiny Tots Survey and the School Skin Survey, the parents of the children and the adolescents themselves were asked before the examination whether they currently had a number of the common skin conditions (with prompting for specific conditions). Overall, 49% of pre-school children aged from birth to five years were reported to have some skin disease by their parents. Self-report of skin disease, or parental report, revealed that 54%

Table 2 — Skin diseases in preschool children reported by their parents* Prevalence % Overall Eczema/dermatitis Seborrhoeic dermatitis/ cradle cap Nappy rash/ diaper dermatitis Tinea/ringworm

of school children aged four to 18 years currently had at least one of the common skin conditions. A breakdown of these conditions can be seen in Tables 2 and 3. In both the Tiny Tots Survey and the School Survey, the self-report of skin disease was followed up with an examination by one of the dermatological team. This confirmed whether the condition that they had reported was present, and whether any other conditions were also present at the time of examination. Confirmation of the self-reported diagnoses revealed underestimates by self-report on some occasions and overestimate on others, with no clear trend. In other words, self-report is one of the ways of estimating morbidity, but there will be inaccuracies in both the diagnosis and the frequency with which people report that they have conditions. In summary, a substantial proportion of the community report that they are currently suffering from at least one skin disease. They also report that they have suffered from a variety of skin diseases in the past. Although crude, this estimate of frequency and morbidity related to skin conditions in the community begins to give an idea of the huge number of people who are affected. It also gives some measure of the morbidity that is related to these common cutaneous conditions.

Table 3 — Skin diseases in school children reported by themselves or their parents*

(95% CI)

49.1 29.4

(46.1-52.1) (26.7-32.1)

19.5

(17.2-21.9)

15.0 0.9

(12.9-17.1) (0.5-1.7)

Prevalence % Overall Acne/pimples Eczema/dermatitis Tinea/ringworm Warts/papilloma

53.6 29.6 15.6 7.8 19.0

(95% CI) (51.6-55.6) (21.0-38.2) (13.9-17.3) (6.4-9.1) (17.0-21.0)

* A number of children had more than one condition.

—— What Skin Diseases Do People Say They Have? ——

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What Skin Diseases Do People Really Have? ACNE Clinical features Acne (pimples) is a common skin condition characterised by the presence of various spots called comedones (blackheads and whiteheads), papules, pustules, and, in severe cases, nodules and cysts. The development of acne coincides with the onset of puberty when androgen hormones, such as testosterone, are released. These hormones can cause the sebaceous glands to overproduce sebum (oil), which leads to blockage and the typical spots associated with acne. Even though many consider acne to be a normal part of growing up, it can have serious effects on a young person’s academic performance and their ability to interact socially. Prevalence of acne in school children 100

Overall Male Female

Prevalence (%)

80 60 40 20 0 4–6

7–9

10–12

13–15

Age (years) Prevalence of acne in school children

Age (years)

No. examined Prevalence % (95% CI) Overall Male Female 4-6 7-9 10-12 13-15 16-18

2491 1174 1317 385 665 636 539 266

36.1 30.7 41.2 0.0 3.0 27.7 78.2 93.3

(24.7-47.5) (19.2-42.3) (29.1-53.3) (0.0-0.0) (1.5-4.6) (20.6-34.8) (73.8-82.6) (89.6-96.9)

Age (years)

Severity of acne in school children

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Overall Male Female 7-9 10-12 13-15 16-18

No. with acne

Minimal %

Mild %

Moderate–severe %

873 362 511 19 188 418 248

40.4 34.3 44.8 94.7 59.6 37.3 27.0

43.1 41.7 44.0 5.3 37.8 43.5 49.2

16.5 24.0 11.2 0.0 2.7 19.1 23.8

—— Atlas Of Common Skin Diseases ——

16–18

Prevalence of acne in adults 50 45 40

30 25 20 15 10 5 0 20–29

30-–39

40–49

50–49

Age (years) Prevalence of acne in adults

60–69

70+

Overall Male Female

Age (years)

No. examined Prevalence % (95% Cl) Overall Male Female 20-29 30-39 40-49 50-59 60-69 70+

1,457 670 787 156 211 272 267 268 283

12.8 11.8 13.6 42.0 23.9 8.6 3.1 1.4 0.4

(11.0-14.5) (9.4-14.2) (11.2-16.1) (35.4-48.6) (18.6-29.3) (5.2-11.9) (1.6-6.0) (0.5-4.3) (0.1-2.8)

Severity of acne in adults No. with acne

Age (years)

Prevalence (%)

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Overall Male Female 20-29 30-39 40-49 50-59 60-69 70+

150 63 87 65 49 23 9 3 1

Mild % 81.2 81.2 81.1 72.5 90.8 88.9 75.2 100.0 100.0

Moderate %

Severe %

17.0 17.4 16.7 24.7 9.2 7.8 24.8 0.0 0.0

1.8 1.3 2.2 2.8 0.0 3.3 0.0 0.0 0.0

—— Acne ——

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Prevalence of acne in school children and adults 100

Overall Male Female

Prevalence (%)

80

60

40

20

0 5

11

17

25

35

45

55

65

75+

Age (years)

The Acne Disability Index (ADI) in school students with acne ADI question

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Answer

% (n=382)

1.

As a result of having acne/ pimples, during the last month have you been aggressive, frustrated or embarrassed ?

Very much indeed ......................... A lot................................................ A little............................................. Not at all ........................................

2.6 4.2 27.0 66.2

2.

Do you think that having acne/ pimples during the last month interfered with your daily social life, social events or relationships with members of the opposite sex ?

Severely, affecting all activities...... Moderately, in most activities ........ Occasionally or in only some activities.................................... Not at all ........................................

1.0 3.1

3.

During the last month have you avoided public changing facilities or wearing swimming costumes because of your acne/pimples ?

All of the time................................ Most of the time ............................ Occasionally ................................... Not at all ........................................

1.0 0.3 5.0 93.7

4.

How would you describe your feelings about the appearance of your skin over the last month ?

Very depressed and miserable....... Usually concerned .......................... Occasionally concerned.................. Not bothered ..................................

2.1 12.6 37.4 47.9

5.

Please indicate how bad you think your acne/pimples is now:

The worst it could possibly be ...... A major problem ............................ A minor problem ............................ Not a problem ................................

0.8 8.4 43.5 47.3

—— An Atlas of Common Skin Diseases ——

15.4 80.5

Frequency, severity and morbidity The data show that acne is most common in adolescence. It is more common in younger females due to early onset of puberty. It increases in frequency and severity in males in later adolescence. Even though it has traditionally been called a disease of adolescence, a substantial proportion of young adults in their twenties and thirties also suffer from acne to some degree. More than 15% of school children had acne that was classified as moderate to severe requiring medical care. Greater than 25% were in this category between 20-29 years. The acne disability index is a quality of life measure asking questions related specifically to the nature of acne. More than 30% of school students had felt aggressive, frustrated or embarrassed about the condition. A similar proportion was seen in adults using the DLQI. Twenty percent of school students stated that their social life or relationships with others had been affected and more than 50% of students had been concerned because of their skin in the last month. Over 40% of the adults affected had symptoms such as pain, stinging or soreness related to their acne within the last week.

The Dermatology Life Quality Index (DLQI) in adults with acne DLQI question

ANSWERS

Over the last week…

very much

a lot

% (n=122) a little not at all / not relevant

1.

how itchy, sore, painful or stinging has your skin been?

1.6

4.1

37.7

56.6

2.

how embarrassed or self-conscious have you been because of your skin?

2.5

4.1

30.3

63.1

3.

how much has your skin interfered with you going shopping or looking after your home or garden?

0.0

0.0

3.3

96.7

how much has your skin influenced the clothes you wear?

0.8

1.6

5.7

91.8

how much has your skin affected any social or leisure activities?

0.8

0.0

1.6

97.5

how much has your skin made it difficult for you to do any sport?

0.0

0.0

1.6

98.4

how much has your skin been a problem at work or studying?

0.0

0.8

3.3

95.9

how much has your skin created problems with your partner or any of your close friends or relatives?

0.0

0.0

4.1

95.9

how much has your skin caused any sexual difficulties?

0.0

0.0

3.3

96.7

0.0

0.0

5.7

94.3

4. 5. 6. 7. 8.

9.

10. how much of a problem has the treatment for your skin been, for example, by making your home messy, or by taking up time?

—— Acne ——

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NAPPY RASH

(NAPKIN DERMATITIS)

Clinical features Nappy rash is an inflammatory skin condition localised to the nappy area. It is usually red and can cause discomfort in the infant or toddler affected. It is caused by contact with urine and faeces which are irritating substances, and occurs on areas of the skin which are in contact with the nappy. The deep skin folds in the groin may therefore not be affected. Other types of eczema or dermatitis such as atopic dermatitis and seborrhoeic dermatitis, can occur in the nappy area and may be associated with an increased tendency to nappy rash.

Prevalence of nappy rash in infants 40 35

Prevalence (%)

30 25 20 15 10 5 0