Psoriasis in Norway as observed in a population-based Norwegian twin panel

Sex- and gender-associated clinical and psychosocial characteristics of patients with psoriasis

BACKGROUND

Sex and gender may affect disease prevalence, adverse effects and response to therapy.

AIM

To analyse sex and gender differences in outpatients with psoriasis.

METHODS

A cross-sectional study was conducted at IDI-IRCCS, Rome, over a 3-year period. In total, 3023 patients with psoriasis were enrolled. Anthropometric and demographic characteristics were recorded, and a dermatologist evaluated the clinical severity of disease. Quality of life (QoL) questionnaires were collected. Univariate and multivariate analyses were performed to examine factors associated with sex.

RESULTS

We found sex- and gender-associated differences in clinical characteristics, disease severity, psychological distress and quality of life. Male sex was associated with body mass index, smoking, alcohol consumption, Psoriasis Area Severity Index ≥ 10 and age at onset ≥ 20 years. Female sex was associated with family history of diabetes, joint involvement, clinical type other than diffuse plaque psoriasis, higher psychological distress and a greater effect on QoL.

CONCLUSION

Our study identified sex and gender differences of potential clinical relevance in psoriasis.

Psoriasis, cardiovascular risk factors and metabolic disorders: sex-specific findings of a population-based study

BACKGROUND

Scientific evidence suggests an association between psoriasis and cardiovascular and metabolic diseases. However, there are hardly any sex-specific results from population-based studies reporting the prevalence of cardiovascular risk factors in patients with psoriasis and point estimates of the association between psoriasis and cardiovascular and metabolic disorders.

OBJECTIVE

Aims are to evaluate the sex-specific prevalence of psoriasis and cardiovascular risk factors, and to estimate sex-specific associations between psoriasis and diabetes type 2 (DM) and metabolic syndrome (MetS).

METHODS

We used data of 3723 participants (45-75 years, 54.1% women) without coronary heart disease and missing data (psoriasis, DM, MetS) from the Heinz Nixdorf Recall study. Standardized information on health outcomes and risk factors was assessed. We performed descriptive statistics and multiple regression analyses to calculate prevalence rate ratios (PR) and 95% confidence intervals (95% CI).

RESULTS

The prevalence of psoriasis was 3.8% (n = 143), with no differences between sex. We observed more often metabolic and cardiovascular risk factors in women with psoriasis compared to women without psoriasis. Interestingly, in men, this pattern was partly reversed. Multiple regression analyses revealed distinctly elevated PRs for DM for both women and men with psoriasis (fully adjusted PR: 2.43; 95% CI: 1.17-5.07, resp. 2.09; 1.16-3.76). Regarding the MetS, the results were inconsistent, showing a positive association between psoriasis and MetS in women (1.84; 1.14-2.98), but a negative association in men, even though with a wide 95% CI (0.69; 0.42-1.12).

CONCLUSION

The results of our cross-sectional, population-based analysis show a distinct association between psoriasis and DM, whereas for the MetS the results contrasted between men and women, translating in women with MetS showing a higher and in men a lower chance to be psoriatic. Our results emphasize the urgent need for sex-specific research, studying the effects of psoriasis on metabolic disorders as well as effective sex tailored prevention measures.

A retrospective cohort study to evaluate the development of comorbidities, including psychiatric comorbidities, among a pediatric psoriasis population

BACKGROUND/OBJECTIVE

Compared with the adult psoriasis population, knowledge about the incidence of comorbidities in the pediatric psoriasis population is limited. The objective of this study was to assess the prevalence and incidence of comorbidities, including psychiatric comorbidities, in patients with pediatric psoriasis.

METHODS

In this claims-based, retrospective cohort study, patients with pediatric psoriasis were matched 1:3 with a nonpsoriasis cohort based on age, sex, and index date (the earliest of inpatient claims or the latter of two outpatient claims).

RESULTS

Obesity, serious infection, and juvenile idiopathic arthropathy had higher prevalence and incidence rates in the psoriasis cohort than the nonpsoriasis cohort. Psychiatric comorbidities were also more common in the psoriasis cohort than the nonpsoriasis cohort, as were ulcerative colitis and Crohn disease. Stratifying the psoriasis cohort by disease severity-mild and moderate-to-severe-found no differences in incidence rates of comorbidities between the two subsets.

CONCLUSION

The incidence rates of many comorbid conditions were higher for patients with pediatric psoriasis compared with patients without pediatric psoriasis, and similar between patients with moderate-to-severe and mild pediatric psoriasis.

Epidemiology and Clinical Features of Adult Patients with Psoriasis in Malaysia: 10-Year Review from the Malaysian Psoriasis Registry (2007-2016)

Background

Psoriasis is a chronic inflammatory skin disease affecting 2-3% of the general population.

Aim

To evaluate the epidemiology and clinical characteristics of patients with psoriasis who seek treatment in outpatient dermatology clinics throughout hospitals in Malaysia.

Materials and Methods

Data were obtained from the Malaysian Psoriasis Registry (MPR). All patients (aged 18 and above) who were notified to the registry from July 2017 to December 2017 were included in this study.

Results

Among 15,794 patients, Malays were the most common (50.4%), followed by Chinese (21.4%), Indian (17.6%), and others (10.6%). The mean age onset of psoriasis for our study population was 35.14 ± 16.16 years. Male to female ratio was 1.3 : 1. 23.1% of patients had positive family history of psoriasis. The most common clinical presentation was chronic plaque psoriasis (85.1%), followed by guttate psoriasis (2.9%), erythrodermic psoriasis (1.7%), and pustular psoriasis (1.0%). Majority of our patients (76.6%) had a mild disease with BSA < 10%. 57.1% of patients had nail involvement, while arthropathy was seen in 13.7% of patients. Common triggers of the disease include stress (48.3%), sunlight (24.9%), and infection (9.1%). Comorbidities observed include obesity (24.3%), hypertension (25.6%), hyperlipidemia (18%), diabetes mellitus (17.2%), ischaemic heart disease (5.4%), and cerebrovascular disease (1.6%). The mean DLQI (Dermatology Life Quality Index) was 8.5 ± 6.6. One-third (33.1%) of the patients had a DLQI score of more than 10, while 14.2% of patients reported no effect at all.

Conclusion

Our study on the epidemiological data of adult patients with psoriasis in Malaysia showed a similar clinical profile and outcome when compared to international published studies on the epidemiology of psoriasis.

A systematic review of worldwide epidemiology of psoriasis

To inform the WHO Global report on psoriasis, a new comprehensive worldwide systematic review of the epidemiology of psoriasis was undertaken. The aim of this study was to systematically review the worldwide literature regarding the epidemiology of psoriasis, including prevalence and incidence, in adults and in children. A search of 15 electronic medical databases was performed. Using a rigorous systematic protocol, eligible articles were analysed. No language, regional or temporal restrictions were applied. A total of 76 study observations met all eligibility criteria and were included in the systematic review. The estimates of the prevalence of psoriasis in adults ranged from 0.51% to 11.43%, and in children from 0% to 1.37%. Psoriasis is a common disease, occurring more frequently with advancing age. Limited data on the epidemiology of psoriasis are available. The available prevalence data come from only 20 countries, meaning there are huge geographic gaps in knowledge, especially from low- and middle-income settings.

Elevated odds of metabolic syndrome in psoriasis: a population-based study of age and sex differences

BACKGROUND

Questions remain concerning to what extent age and sex may modify the suggested association between psoriasis and the metabolic syndrome in the general population.

OBJECTIVES

To investigate the association between psoriasis and the metabolic syndrome within a large population-based cohort by age and sex.

METHODS

A cross-sectional study including 10 521 participants aged 30-79 years from the Tromsø Study cohort was performed; 1137 participants reported lifetime psoriasis of a mainly mild character. The new harmonized definition of metabolic syndrome was used in the multivariable logistic regression analysis.

RESULTS

There was a uniformly higher prevalence of metabolic syndrome in men and women with psoriasis compared with those without across all age groups. In women, psoriasis was associated with a 3·8-times higher odds of metabolic syndrome at age 30 years (95% confidence interval 1·5-9·7), with a decreasing odds ratio with increasing age. In men, psoriasis was associated with a stable 1·35-times higher odds of metabolic syndrome (95% confidence interval 1·1-1·6) at all ages. Abdominal obesity was the most frequent metabolic syndrome component in women in this study, and there was indication of a dose-response relationship between psoriasis severity, indicated through treatment, and having a high waistline in women.

CONCLUSIONS

This study suggests age and sex variations in the risk of metabolic syndrome among individuals with psoriasis. Given the high prevalence of psoriasis and the significantly elevated burden of metabolic syndrome in this patient group, there may be a benefit from targeted screening of metabolic syndrome among individuals with psoriasis regardless of age and disease severity.

The Norwegian Twin Registry from a Public Health Perspective: A Research Update

We describe the importance of the Norwegian Twin Registry (NTR) for research in public health and provide examples from several programs of twin research at the Norwegian Institute of Public Health (NIPH), including the Nordic Twin Study of Cancer, our epigenetics platform, and our large program of research in mental health. The NTR has become an integral component of a national strategy for maximizing the research potential from Norwegian registries and biobank-based studies. The information provided herein builds upon and complements our recent report describing the establishment of the NTR and the cohorts comprising it. Although Norway has a long tradition in twin research, the centralization and administration of the twin data through a single register structure is fairly recent. The NTR was established in 2009 and currently includes 47,989 twins covering birth years 1895–1960 and 1967–1979; 31,440 of these twins have consented to participate in medical research (comprising 5,439 monozygotic pairs, 6,702 dizygotic same-sexed pairs, and 1,655 dizygotic opposite-sexed pairs). DNA from approximately 4,800 twins is banked at the NIPH biobank and new studies continuously add new data to the registry. The value of NTR data is greatly enhanced through record linkage possibilities offered by Norway's many nation-wide registries (medical, demographic, and socio-economic) and several studies are already taking advantage of these linkage opportunities for research.

Depression and the risk of psoriasis in US women

BACKGROUND

Depression is a common mental health condition that has been associated with psoriasis. In the absence of prospective data, it remains unclear whether depression precedes psoriasis as a risk factor.

OBJECTIVES

To examine the association between depression and the risk of new-onset psoriasis.

METHODS

A prospective cohort of 86 880 US female nurses, The Nurses' Health Study II, was followed up from 1993 to 2005. Participants reported anti-depressant use and completed the Mental Health Index (MHI), a subscale of the Short-Form 36 in 1993. The MHI assessed for depression and scores was categorized into four strata: 0-52, 53-75, 76-85 and 86-100, with lower scores associated with increasing depressive symptoms. We excluded participants with a history of psoriasis prior to 1993. A self-report of incident physician-diagnosed psoriasis constituted the main outcome measure. For a sensitivity analysis, we had a subset of confirmed psoriasis cases.

RESULTS

Depression was associated with an increased risk of incident psoriasis. Compared to women in the non-depressed group (MHI 86-100), women who reported either having high depressive symptomatology (MHI scores < 52) or who were on anti-depressants had a multivariate relative risk (RR) of 1.59 for developing subsequent psoriasis (95% confidence interval [CI], 1.21-2.08). These associations became stronger among confirmed psoriasis cases.

CONCLUSIONS

We found that depression was independently associated with an increased risk of psoriasis in this population of US women.

The Norwegian Institute of Public Health Twin Program of Research: An Update

The population-based twin program of research at the Norwegian Institute of Public Health (NIPH) was begun in 1992. It consists of a number of questionnaire and clinical interview projects exploring a broad array of mental and physical health outcomes. This article provides a brief update summarizing our research activities, some research highlights, new developments and potentials for further developing the program of twin research. In the most recent years a large effort has concentrated on completing a mental health interview study of Axis I psychiatric and substance use disorders and Axis II personality disorders. Although still in the early planning phases, one of the most significant developments is that an agreement is now in place to centralize the Norwegian twin data into a national Norwegian Twin Registry. This new registry will include twin cohorts born from 1905 onwards. Other resources for building twin projects are described. Nationally, there is great potential for linking the NIPH twin data with other health registries and with information in a number of Norway's large population-based biobank studies. Internationally, platforms such as those developed within GenomEUtwin, for data standards and data sharing and access are greatly facilitating international collaborations in twin research.

Alcohol intake and risk of incident psoriasis in US women: a prospective study

OBJECTIVES

To evaluate the independent association between alcohol consumption and risk of developing psoriasis and to determine if this risk is associated with different types of alcoholic beverages.

DESIGN

A prospective study of female nurses who were followed up from 1991 to 2005.

SETTING

Nurses' Health Study II, a cohort of 116,671 US women aged 27 to 44 years in 1991.

PARTICIPANTS

The study population included 82,869 women who reported amount and type of alcohol intake on biennial questionnaires. We excluded participants with a history of psoriasis prior to 1991.

MAIN OUTCOME MEASURE

Self-report of incident physician-diagnosed psoriasis. For a sensitivity analysis, we had a subset of confirmed psoriasis cases.

RESULTS

There were 1150 cases of incident psoriasis, 1069 of which were used for analysis. Compared with women who did not drink alcohol, the multivariate relative risk (RR) of psoriasis was 1.72 (95% confidence interval [CI], 1.15-2.57) for an alcohol consumption of 2.3 drinks/wk or more. When examined by type of alcoholic beverage, there was an association between psoriasis and nonlight beer intake (multivariate RR for ≥ 5 drinks/wk, 1.76; 95% CI, 1.15-2.69); light beer, red wine, white wine, and liquor were not significantly associated with psoriasis risk. The association with nonlight beer intake became stronger in a subset of confirmed psoriasis cases (multivariate RR for ≥ 5 drinks/wk, 2.29; 95% CI, 1.36-3.85).

CONCLUSIONS

Nonlight beer intake is associated with an increased risk of developing psoriasis among women. Other alcoholic beverages did not increase the risk of psoriasis in this study.

Geoepidemiology and environmental factors of psoriasis and psoriatic arthritis

Psoriasis and Psoriatic Arthritis (PsA) are chronic inflammatory diseases that have a major impact on health. The prevalence and incidence estimates of these two closely related diseases show ethnic and geographic variations, being generally more common in the colder north than in the tropics. In Europe the prevalence of psoriasis varies anywhere from 0.6 to 6.5%. In the USA, the estimated prevalence of diagnosed psoriasis is 3.15%. The prevalence in Africa varies depending on geographic location, being lowest in West Africa. Psoriasis is less prevalent in China and Japan than in Europe, and is entirely absent in natives of the Andean region of South America. There are fewer reports on the incidence of psoriasis, but a recent study from Rochester, USA showed an increasing trend over the last 2 decades. The prevalence of PsA also shows similar variation, being highest in people of European descent and lowest in the Japanese. Although, study methodology and case definition may explain some of the variations, genetic and environmental factors are important. Genetic epidemiologic studies have shown that both diseases have a strong genetic component. The strongest association is with HLA-Cw*06. Associations with a number of genes including IL12B and IL23R have recently been confirmed. Environmental risk factors including streptococcal pharyngitis, stressful life events, low humidity, drugs, HIV infection, trauma, smoking and obesity have been associated with psoriasis and PsA. Here we have reviewed the current literature on the epidemiology and genetics of psoriasis and PsA.

Psoriasis in Norwegian twins: contribution of genetic and environmental effects

BACKGROUND

Psoriasis is a chronic T-cell-mediated immunological skin disease with a complex pathogenesis where both genetic and environmental factors are involved.

OBJECTIVE

To study the conditional and relative risk of developing psoriasis in identical and fraternal twins whose co-twin has a positive history of the disease and to estimate the relative contribution of genetic and environmental factors on the liability for psoriasis in Norway.

METHODS

Self-reported history of psoriasis in twins from the population-based Norwegian Twin Panel (N = 8045) was studied. Absolute and relative risks of developing psoriasis conditioned on the positive history of psoriasis in a co-twin were calculated by Kaplan-Meier survival analysis and Cox regression, respectively. Structural equation modelling was used to estimate genetic and environmental variance components.

RESULTS

Altogether, 334 (4.2%) of the twins reported having psoriasis. No difference in prevalence of the disease across sexes and zygosity groups was found. Identical twins were more likely to develop psoriasis than fraternal twins if a co-twin reported having the disease. The best-fitting model showed that additive genetic effects could explain 66% of the variation in liability for psoriasis in this population, and the remaining 34% was due to non-shared environmental influences.

CONCLUSIONS

High heritability due to additive genetic effects together with considerable environmental contribution to the liability of psoriasis support the current opinion on the multifactorial aetiology of the disease. No sex-specific patterns of heritability of psoriasis were found.