Diet and nutrition in psoriasis: analysis of the National Health and Nutrition Examination Survey (NHANES) in the United States

Psoriasis and risk of chronic kidney diseases: A population-based cross-sectional study and Mendelian randomization analysis

BACKGROUND

Conflicting results have been reported regarding the association between psoriasis and risk of chronic kidney diseases (CKD). Furthermore, the causal nature of the possible association remains unexplored.

METHODS

We conducted a population-based cross-sectional study using data from National Health and Nutrition Examination Survey (NHANES). Logistic regression analyses were conducted to estimate potential association between psoriasis and CKD risk. Further, we evaluated causality by performing a Mendelian randomization analysis using large-scale genome-wide association studies of psoriasis and CKD. Inverse variance-weighted (IVW) analysis was used as the primary method.

RESULTS

In the observational study, 16 750 participants were included. Overall, 39 of 429 patients with psoriasis had CKD (9.1%) compared with 1481 of 16 321 without psoriasis (9.1%). In the fully adjusted model, psoriasis was not associated with CKD (OR: 0.77, 95%CI: 0.53-1.10). In the MR analysis, 36 single-nucleotide polymorphisms (SNPs) were selected as instrumental variables. The IVW analysis reported that genetically predicted psoriasis was associated with a higher risk of CKD (OR: 1.025, 95%CI: 1.001-1.049). After removing 2 SNPs associated with heterogeneity, the association remained (OR: 1.028, 95%CI: 1.006-1.050).

CONCLUSION

Genetically predicted psoriasis was associated with a higher risk of CKD. This association may be important for clinicians to monitor kidney function and prescribe potentially nephrotoxic drugs during psoriasis management.

Effect of low-calorie diet on psoriasis severity index, triglycerides, liver enzymes, and quality of life in psoriatic patients with non-alcoholic fatty liver disease

Introduction

Chronic-plaque psoriasis is a chronic inflammatory dermatological disease. Obesity comorbidities, including non-alcoholic fatty liver disease, are highly prevalent in patients with chronic-plaque psoriasis. Recently, weight loss has been a highly recommended intervention to improve the severity of psoriatic symptoms, psoriasis-induced chronic systemic inflammation, psoriasis-associated cardiovascular risk factors, quality of life, and the efficacy of anti-psoriatic drugs. This study was designed to assess the effect of a 12-week low-calorie-diet intervention on aspartate transaminase, psoriasis severity (assessed via Psoriasis Area and Severity Index - PASI), alanine transaminase, quality of life (assessed via Dermatology Life Quality Index - DLQI), triglycerides, waist circumference (WC), and body mass index (BMI) in class I obese men with chronic-plaque and non-alcoholic fatty liver disease.

Material and methods

Sixty men with age ≥ 18 years with class I obesity and with chronic plaque psoriasis and non-alcoholic fatty liver disease were included in the study. All participants were randomly assigned to one of two groups: the first group as the low-calorie-diet group (30 men received immunosuppressive drugs, followed a low-calorie diet, and increased their energy expenditure through a daily 15,000-step outdoor walking program for 12 weeks) and the second as the control group (30 men received immunosuppressive drugs only). The primary outcome consisted of the results of the area and severity index. Weight, BMI, WC, laboratory results such as triglycerides, liver enzymes (alanine transaminase and aspartate transaminase) as well as DLQI were considered as secondary outcomes.

Results

While no significant improvements were achieved in the measured variables of the control group, the low-calorie-diet group demonstrated significant improvement in all the measured variables.

Conclusions

The results of the present study confirmed that 12-week low-calorie-diet intervention controls BMI, increases the response of psoriasis to pharmacological agents and improves the quality of life. Diet interventions significantly control the elevated hepatic enzymes (aspartate and alanine transaminases) and triglycerides in male patients with chronic-plaque psoriasis and non-alcoholic fatty liver disease.

Assessment of cytochrome P450 1A1 gene polymorphism and vitamin A serum level in psoriasis vulgaris

Psoriasis is characterized by cutaneous hyperproliferation, secondary to immune system dysregulation. Vitamin A regulates the immune response and sustains epithelial tissue hemostasis. The CYP1A1 gene, has many biological actions, including vitamin A metabolism. To evaluate CYP1A1 gene polymorphism and serum vitamin A level in patients with psoriasis vulgaris, a case-control study involving two groups was conducted: group 1 (45 patients with psoriasis vulgaris) served as the cased group and group 2 (45 healthy participants who were sex and age matched) acted as the control group. CYP1A1 (rs1048943) gene polymorphism and vitamin A serum level were assessed by TaqMan allelic discrimination (PCR) and ELISA, respectively. AG genotype was present only in cases (22.2%), while AA genotype was present in all controls (P=.001). Vitamin A levels were lower in cases than in controls (32.0 ± 7.41 vs. 46.2 ± 15.7 μg/ml, respectively) (P<.001). AG genotype was associated with a lower vitamin A level (P=.001). The detected genotype difference between psoriasis patients and controls, which was associated with a lower serum vitamin A level and was also lower in more severe cases, suggests a role of the CYP1A1 gene and vitamin A in disease pathogenesis and prognosis.

Effect of diet and weight loss on the severity of psoriasis

Psoriasis is one of the most common chronic inflammatory skin diseases, constituting a significant health and socioeconomic problem. Despite numerous therapeutic options, the results of treatment often remain insufficient. This may be due to the lack of compliance with medical prescriptions and patients’ limited knowledge of their disease. Psoriatic patient's skin well-being is affected by many factors, including lifestyle. The course of the disease is affected by obesity, improper diet, and stimulants. Often these factors coexist. Excessive weight gain in psoriasis can be caused by a decrease in physical activity, caused by feelings of social stigma, coexistence of psoriatic arthritis, depression, and increased alcohol consumption. Several studies have confirmed that the average fat, protein, and calorie content in the diet of a patient with psoriasis are above the recommended norms. On the other hand, adhering to a low calorie, reducing diet results in a clinically significant improvement in the Psoriasis Area Severity Index (PASI) and patients’ quality of life (i.e., reduction of Dermatology Life Quality Index [DLQI]). Weight reduction caused by diet and exercise reduces the severity of skin lesions, even in people who have not achieved improvement after general treatment. Therefore, it is important to educate the patient about the nature of the disease at the very beginning of treatment. Patients with moderate to severe forms of the disease are predisposed to the development of cardiovascular diseases, obesity, diabetes, and anxiety. That is why plaque psoriasis requires a comprehensive treatment and a holistic approach to the patient.

Association Between Daily Dietary Eicosatetraenoic Acid Intake and the Lower Risk of Psoriasis in American Adults

Purpose

Unlike eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the relationship between eicosatetraenoic acid (ETA) and psoriasis remains unclear. Therefore, We performed a cross-sectional study in the general American population to investigate the association between daily dietary ETA, EPA, and DHA intake and the risk of psoriasis.

Participants and Methods

This study applied data from the National Health and Nutrition Examination Survey (NHANES) 2003-2006 and 2009-2014. Dietary n3 polyunsaturated fatty acids (PUFA) were calculated based on two 24-hour dietary recall interviews. We defined psoriasis by responding to the question "Have you ever been told by a doctor or other health care professional that you had psoriasis?". Multivariable logistic regression analysis, trend tests, subgroup analysis, and interaction tests were used to evaluate the associations of ETA, EPA, and DHA intake with the risk of psoriasis, respectively.

Results

A total of 15,733 participants were included in this study. In our optimal multivariate-adjusted model, the odds ratio (OR) with 95% confidence interval (CI) of psoriasis were 0.30 (0.12, 0.88), 1.92 (0.78, 4.74), 1.28 (0.72, 2.27) for daily dietary ETA, EPA, and DHA intake, respectively. Trend tests showed a dose-effect relationship between daily dietary ETA intake and the lower risk of psoriasis. Subgroup analysis and tests for interaction showed that the association was stable in different subgroups.

Conclusion

Our study revealed that there might be a dose-effect association of daily dietary ETA intake with the lower risk of psoriasis in American adults.

Pathogenesis of psoriasis in the "omic" era. Part III. Metabolic disorders, metabolomics, nutrigenomics in psoriasis

Psoriasis is a systemic disease that is strictly connected with metabolic disorders (insulin resistance, atherogenic dyslipidemia, arterial hypertension, and cardiovascular diseases). It occurs more often in patients with a more severe course of the disease. Obesity is specially an independent risk factor and it is associated with a worse treatment outcome because of the high inflammatory activity of visceral fatty tissue and the production of inflammatory mediators involved in the development of both psoriasis and metabolic disorders. However, in psoriasis the activation of the Th17/IL-17 and the abnormalities in the Th17/Treg balance axis are observed, but this pathomechanism does not fully explain the frequent occurrence of metabolic disorders. Therefore, there is a need to look for better biomarkers in the diagnosis, prognosis and monitoring of concomitant disorders and therapeutic effects in psoriasis. In addition, the education on the use of a proper diet as a prophylaxis for the development of the above disorders is an important element of holistic care for a patient with psoriasis. Diet may affect gene expression due to epigenetic modification which encompasses interactions of environment, nutrition and diseases. Patients with psoriasis should be advised to adopt proper diet and dietician support.

Nutrition and Psoriasis

Psoriasis is a chronic inflammatory skin disease characterized by accelerated tumor necrosis factor-α/interleukin-23/interleukin-17 axis, hyperproliferation and abnormal differentiation of epidermal keratinocytes. Psoriasis patients are frequently associated with obesity, diabetes, dyslipidemia, cardiovascular diseases, or inflammatory bowel diseases. Psoriasis patients often show unbalanced dietary habits such as higher intake of fat and lower intake of fish or dietary fibers, compared to controls. Such dietary habits might be related to the incidence and severity of psoriasis. Nutrition influences the development and progress of psoriasis and its comorbidities. Saturated fatty acids, simple sugars, red meat, or alcohol exacerbate psoriasis via the activation of nucleotide-binding domain, leucine-rich repeats containing family, pyrin domain-containing-3 inflammasome, tumor necrosis factor-α/interleukin-23/interleukin-17 pathway, reactive oxygen species, prostanoids/leukotrienes, gut dysbiosis or suppression of regulatory T cells, while n-3 polyunsaturated fatty acids, vitamin D, vitamin B12, short chain fatty acids, selenium, genistein, dietary fibers or probiotics ameliorate psoriasis via the suppression of inflammatory pathways above or induction of regulatory T cells. Psoriasis patients are associated with dysbiosis of gut microbiota and the deficiency of vitamin D or selenium. We herein present the update information regarding the stimulatory or regulatory effects of nutrients or food on psoriasis and the possible alleviation of psoriasis by nutritional strategies.

Importance of Redox Equilibrium in the Pathogenesis of Psoriasis-Impact of Antioxidant-Rich Diet

Psoriasis is a common, chronic, hyperproliferative, inflammatory skin disease occurring in most ethnic groups in the world. The disease is hereditary but the process of its inheritance is complex and still not fully understood. At the same time, it has been observed that psoriatic lesions may be triggered by certain prooxidative external factors: using narcotics, smoking, drinking alcohol, physical and mental stress, as well as bacterial infections and injury. Since the main physiological marker of psoriasis relates to disorders in the organism's antioxidative system, it is necessary to develop a well-balanced combination of pharmaceuticals and dietary antioxidants to facilitate the effective treatment and/or prevention of the disease. The dietary sources of antioxidants must be adequate for chronic use regardless of the patient's age and be easily available, e.g., as ingredients of regular food or dietary supplements. Diet manipulation is a promising therapeutic approach in the context of modulating the incidence of chronic diseases. Another potentially viable method entails the use of nutrigenomics, which guarantees a multiaspectual approach to the problem, including, in particular, analyses of the genetic profiles of psoriasis patients with the view to more accurately targeting key problems. The present paper pertains to the significance of redox equilibrium in the context of psoriasis. Based on information published in worldwide literature over the last decade, the impact of dietary exogenous antioxidants on the course of this chronic disease was analysed.

A Comparison of The Effects of Clobetasol 0.05% and Photodynamic Therapy Using Aminolevulinic Acid With Red Light in the Treatment of Severe Nail Psoriasis

Introduction: The treatment of nail psoriasis is often difficult and unsatisfactory due to therapy resistance. This study aimed to compare the efficacy of clobetasol 0.05% ointment and photodynamic therapy (PDT) using aminolevulinic acid (ALA) and red light in the treatment of severe nail psoriasis. Methods: This open-trial study included 69 nails of 8 patients with severe nail psoriasis. Thirty-four nails were treated with clobetasol 0.05% ointment and 35 nails were treated with ALA-PDT. ALAPDT treatment was performed every 3 weeks for 5 cycles; the nails were treated with clobetasol under occlusion every day during the study. All the patients were followed up after 24 weeks. The severity of nail involvement was measured by the Nail Psoriasis Severity Index (NAPSI) scores at the baseline and during the treatment. Results: There were no significant differences in the NAPSI scores between the treatment groups in the baseline and weeks 3, 6 and 9 (all P>0.05), although significant differences were found in weeks 12, 15 and 24 (follow-up) (P<0.001). A significant time-effect improvement was found in all the nailmatrix, nail-bed and total NAPSI scores in both treatment groups (all P<0.001). The patients did not report intense pain and discomfort during irradiation. Conclusion: Clobetasol 0.05% ointment seems to be effective in treating nail psoriasis after a treatment period of 15 weeks. However, the efficacy of ALA-PDT at a 24-week follow-up was greater than that of clobetasol.

Retinol and vitamin A metabolites accumulate through RBP4 and STRA6 changes in a psoriasis murine model

Background

Psoriasis is a common chronic inflammatory skin disease that features the abnormal proliferation of keratinocytes. This proliferation could partly result from disturbances in vitamin A metabolism. Changes in psoriasis patients of the levels of retinol-binding protein 4 (RBP4), a carrier of retinol (vitamin A); transmembrane protein stimulated by retinoic acid 6 (STRA6); and other retinol metabolic molecules have not yet been fully established. Therefore, we investigated vitamin A-related proteins in mice with imiquimod (IMQ)-induced psoriasis.

Methods

Thirty mice were divided into four study groups: two groups underwent IMQ application for 3 or 6 days (groups A and B, respectively), and two groups underwent Vaseline application for 3 or 6 days (groups C and D, respectively). Blood and skin samples from both lesional and non-lesional areas of the mice were analyzed using enzyme-linked immunosorbent assays, hematoxylin and eosin staining, immunochemistry, real-time reverse transcription polymerase chain reaction, and RNA sequencing.

Results

IMQ-treated mice developed erythema, scales, and skin thickening. Compared with the control groups, IMQ-treated groups had the following changes: 1) interleukin (IL)-17A, IL-23, and tumor necrosis factor (TNF)-α levels were raised significantly in both serum and lesional skin (all p < 0.001); 2) retinol levels in lesional skin increased slightly (p = 0.364), but no change was evident in serum retinol levels; 3) STRA6 was upregulated in both lesional skin (p = 0.021) and serum (p = 0.034); 4) RBP4 levels were elevated in serum (p = 0.042), but exhibited only an increasing trend (p = 0.273) in lesional skin; and 5) proteins and enzymes that mediate retinoic acid formation and transformation were upregulated in lesional skin.

Conclusions

As the demand for vitamin A in psoriatic mice increased, retinol underwent relocation from the circulation to target tissues. RBP4, STRA6, and the transformation from retinol to retinoic acid were upregulated, which may be part of the mechanism of psoriasis skin lesion formation. We propose that a positive feedback mechanism was formed that maintained the severity of psoriasis.

Body mass index, abdominal fatness, weight gain and the risk of psoriasis: a systematic review and dose-response meta-analysis of prospective studies

Greater body mass index (BMI) has been associated with increased risk of psoriasis in case–control and cross-sectional studies, however, the evidence from prospective studies has been limited. We conducted a systematic review and dose–response meta-analysis of different adiposity measures and the risk of psoriasis to provide a more robust summary of the evidence based on data from prospective studies. PubMed and Embase databases were searched for relevant studies up to August 8th 2017. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using a random effects model. The summary relative risk (RR) for a 5 unit increment in BMI was 1.19 (95% CI 1.10–1.28, I² = 83%, n = 7). The association appeared to be stronger at higher compared to lower levels of BMI, p_nonlinearity < 0.0001, and the lowest risk was observed at a BMI around 20. The summary RR was 1.24 (95% CI 1.17–1.31, I² = 0%, p_{heterogeneity} = 0.72, n = 3) per 10 cm increase in waist circumference, 1.37 (95% CI 1.23–1.53, I² = 0%, p_{heterogeneity} = 0.93, n = 3) per 0.1 unit increase in waist-to-hip ratio, and 1.11 (95% CI 1.07–1.16, I² = 47%, p_{heterogeneity} = 0.15, n = 3) per 5 kg of weight gain. Adiposity as measured by BMI, waist circumference, waist-to-hip ratio, and weight gain is associated with increased risk of psoriasis.

Dietary Behaviors in Psoriasis: Patient-Reported Outcomes from a U.S. National Survey

INTRODUCTION

Psoriasis patients demonstrate high interest in the role of diet on their skin condition. However, data are lacking to describe dietary interventions among psoriasis patients and associated outcomes. This study aims to identify common dietary habits, interventions and perceptions among patients with psoriasis, and to examine patient-reported skin outcomes in response to these interventions.

METHODS

We administered a 61-question survey to the National Psoriasis Foundation membership asking psoriasis patients about dietary habits, modifications, skin responses, and perceptions.

RESULTS

A total of 1206 psoriasis patients responded to the survey. Compared to age- and sex-matched controls, psoriasis patients consumed significantly less sugar, whole grain fiber, dairy, and calcium (p < 0.001), while consuming more fruits, vegetables, and legumes (p < 0.01). Eighty-six percent of respondents reported use of a dietary modification. The percentage of patients reporting skin improvement was greatest after reducing alcohol (53.8%), gluten (53.4%), nightshades (52.1%), and after adding fish oil/omega-3 (44.6%), vegetables (42.5%), and oral vitamin D (41%). Specific diets with the most patients reporting a favorable skin response were Pagano (72.2%), vegan (70%), and Paleolithic (68.9%). Additionally, 41.8% of psoriasis respondents reported that a motivation for attempting dietary changes was to improve overall health.

CONCLUSION

This national survey is among the first to report the dietary behaviors of patients with psoriasis. The data provided from this large cohort may benefit patients and clinicians as they discuss the role of diet in managing both psoriasis and associated cardiometabolic comorbidities.

Prevalence of weight loss attempts and behaviors used by individuals with psoriasis in the United States population

OBJECTIVE

To examine weight loss behaviors of individuals with psoriasis in the American population and compare them to individuals without psoriasis.

METHODS

An analysis of data from the 2011-2014 National Health and Nutrition Examination Survey (NHANES) was conducted. A total of 9174 Americans were included, with 232 self-reporting psoriasis. Measures included weight history and subjective physical activity, as well as the prevalence of weight loss attempts and weight loss behaviors over the past 12 months.

RESULTS

Participants with psoriasis were no more likely to have attempted to lose weight than participants without psoriasis (46.3 vs. 38.2%, p = .161). Likewise, the proportion of participants with psoriasis desiring to weigh less was similar to those without psoriasis (67.4 vs. 61.9%; p = .277). Only 48.0% of participants with psoriasis employed exercise to lose weight, as compared to 62.4% without psoriasis (p = .027). Among participants that attempted to lose weight, only 16.1% with psoriasis engaged in vigorous recreational physical activity, as compared to 28% of individuals without psoriasis (p = .042).

CONCLUSIONS

Participants self-reporting psoriasis were less likely to use exercise to lose weight. Clinicians should identify physical activity barriers among overweight/obese psoriasis patients, especially among those attempting to reduce weight.

Nutrition: a key environmental dietary factor in clinical severity and cardio-metabolic risk in psoriatic male patients evaluated by 7-day food-frequency questionnaire

Background

Western dietary pattern is included among the environmental dietary factors involved in the pathogenesis of psoriasis. Nutritional data collection methods and gender differences might affect the association between diet and psoriasis. The 7-day food records is considered the “gold standard” of self-administered food frequency questionnaires. In this study, we evaluated the differences in the dietary intake, anthropometric measurements and cardio-metabolic risk profile in a group of psoriatic patients compared with an age and Body Mass Index (BMI)-matched control group. In addition, in the group of psoriatic patients we investigated the association between the dietary intake and clinical severity of psoriasis.

Methods

Cross-sectional case control observational study. A total of 82 adult males, 41 treatment-naïve patients with psoriasis and 41 healthy subjects matched for age and BMI were included in the study. The clinical severity of psoriasis was by assessed by Psoriasis Area and Severity Index (PASI) score. The dietary interview data were collected by a 7-day food records. Anthropometric measures, glucose and lipid profile, liver function tests and C-reactive protein levels were measured. Homeostasis Model Assessment of Insulin Resistance (HoMA-IR), Visceral Adiposity Index (VAI) and the Fatty Liver Index (FLI) were calculated.

Results

Psoriatic patients consumed a higher percentage of total and simple carbohydrates, total fat, polyunsaturated fatty acid (PUFA) and n-6/n-3 PUFAs ratio, and cholesterol, while the consumption of protein, complex carbohydrates, monounsaturated fatty acid (MUFA), n-3 PUFA and fiber was lower than in the control group. In addition, psoriatic patients presented altered anthropometric measurements, glucose and lipid profile, liver function tests, and elevated values of HoMA-IR, VAI and FLI. PASI score well correlated with anthropometric measures, glucose and lipid profile, liver function tests, cardio-metabolic indices, and the dietary components, except for protein and total carbohydrates. At logistic regression analysis between PASI score and MUFA, MetS presence was well predicted only by higher PASI score (OR = 1.794; p = 0.002; CI 1.242–2.591). At multiple regression analysis, MUFA was the best predictor of PASI score (r² = 0.387, β = −0.635, t = −5.127, p < 0.001).

Conclusion

Differences in dietary intake were observed in adult male psoriatic patients compared with the controls. These differences were associated to the severity of the psoriasis and cardio-metabolic risk. FLI represented an early indicator of the cardio-metabolic risk profile in psoriatic patients, and dietary MUFA were major predictor of the clinical severity of psoriasis, while the association between psoriasis and metabolic syndrome appeared to be independent of MUFA intake. The low MUFA consumption might act as a possible adjunctive mechanism in increasing the inflammation milieu of psoriatic patients.

Prevalence of chronic axial pain, inflammatory back pain, and spondyloarthritis in diagnosed psoriasis

OBJECTIVE

To provide prevalence estimates for inflammatory back pain (IBP) and spondyloarthritis (SpA) in those subjects with psoriasis using 2009-2010 National Health and Nutrition Examination Survey (NHANES) data.

METHODS

In the NHANES 2009-2010 sample set, 6,684 persons ages 20-69 years were screened for participation, and 5,103 answered questions regarding onset of back pain, location of pain, and functional limitations. Data set assembly and statistical analysis were performed using SASTM and SUDAAN software. SEs were estimated by Taylor series linearization. The equality of the prevalence estimates for selected variables was tested (univariately) at an alpha level of 0.05 using 2-sided Student's t-test with appropriate degrees of freedom.

RESULTS

A total of 148 persons had self-reported medically diagnosed psoriasis. The psoriasis group versus the nonpsoriasis group had a significantly higher prevalence of axial pain using the 3-month duration criterion (31.1% versus 18.9%; P = 0.04) and alternating buttock pain (7.2% versus 2.4%; P = 0.03) and more frequently met IBP criteria from Berlin criteria 7b and 8a (P = 0.04 and 0.02, respectively). The prevalence of SpA was significantly higher in the psoriasis group versus the nonpsoriasis group when using Amor or European Spondyloarthritis Study Group criteria (14.3% versus 1.5%; P < 0.001). Sudden onset of axial pain was significantly higher in the psoriasis group (23.3% versus 13.0%; P = 0.01).

CONCLUSION

There is a higher prevalence of lower axial pain, IBP, SpA, and alternating buttock pain associated with a prior diagnosis of psoriasis. These data may influence the way psoriasis patients are approached in primary care and specialty clinics.

Outcomes Research in Psoriasis and Psoriatic Arthritis Using Large Databases and Research Networks: A Report from the GRAPPA 2013 Annual Meeting

Advances in healthcare informatics have increased the ability to address real-world, clinically relevant questions using large databases. When examining data sources, researchers and clinicians need to consider data validity, potential sources of misclassification, whether the source is sufficiently powered to detect clinically relevant differences, ability to obtain longitudinal data, containment of patients within a database, and ability to obtain structured point-of-care data. Population-based databases create opportunities for characterizing natural history of psoriatic diseases, conducting comparative effectiveness research, determining comorbidities, and providing epidemiology-based rational approaches to mechanistic investigations. Herein, we discuss the major data sources for clinical research in psoriasis, including electronic medical records, research networks, disease registries, and others.