The role of nutrition and diet in rheumatoid arthritis

A randomised controlled trial of a Mediterranean Dietary Intervention for Adults with Rheumatoid Arthritis (MEDRA): Study protocol

Background

Rheumatoid arthritis (RA) is the most common type of autoimmune arthritis affecting 0.5-1% of the adult population worldwide. While the primary line of treatment of RA includes pharmacological therapies, people living with the condition often seek non-pharmacological therapies such as diet and exercise in an attempt to attenuate their symptoms. Established, evidence-based dietary guidelines for RA are currently lacking. The MEDRA study aims to explore the effectiveness of implementing, via telehealth, a Mediterranean type diet (MedDiet) compared to a standard healthy diet as per the Healthy Eating Guidelines (HEG) in Ireland in terms of differences in physical function and quality of life in adults with RA living in Ireland.

Methods

The MEDRA study is a parallel, randomised controlled trial delivered through telehealth methods. Forty-four eligible participants who have RA will be randomly allocated to either a MedDiet or HEG group for a 12 weeks intervention period. Primary outcome measures include changes in physical function and quality of life, both of which will be measured using validated questionnaires at baseline, six and twelve weeks. Both intervention arms will attend a total five teleconsultations with a Registered Dietitian (RD). The MedDiet intervention arm focuses on recommendations from the traditional Mediterranean diet and HEG intervention arm will use the dietary recommendations as currently advised in Ireland.

Discussion

This study will provide evidence as to whether dietary treatment of RA can improve physical function and quality of life in a small cohort of participants with RA. The results of the study will be disseminated at national scientific conferences and published in peer-reviewed journals.

Ethics

This protocol has been approved by the Education and Health Sciences Research Ethics Committee at the University of Limerick (2020_09_05_EHS) and by the Health Service Executive Mid-Western Regional Hospital Research Ethics Committee (REC Ref 103/19).

Trial registration

ClinicalTrials.gov NCT04262505. Trial registration date: April 2, 2020.

Dietary interventions with or without omega-3 supplementation for the management of rheumatoid arthritis: a systematic review protocol

Background: Rheumatoid arthritis (RA) is an autoimmune disease characterised by swollen and painful joints. It is hypothesised that changes in lifestyle factors such as consuming a healthier diet may  reduce the severity of RA symptoms. People living with RA commonly make alterations to their dietary intake with the hope of improving their symptoms. This systematic review aims to discuss the effects of dietary interventions with and without omega-3 supplementation for the management of rheumatoid arthritis. Methods: A systematic review of randomised controlled trials (RCTs) and non-randomised controlled trials (NRCTs) will be conducted. MEDLINE, EMBASE, The Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Methodology Register) and CINAHL will be searched from inception without using date restrictions. Primary outcomes will include measures of disease activity, inflammation and quality of life among adults living with RA. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the methodological appraisal of the studies will be assessed independently by two different reviewers (TR and AG) using the Cochrane Risk-of-Bias Tool for RCTs, and Risk-of-Bias In Non-Randomised Studies Tool for NRCTs. Ethics and dissemination: Ethical approval is not required for this systematic review. Only publically available data from previously published studies will be used. The findings of this systematic review will be submitted for publication in a peer-reviewed journal and presented at relevant conferences. PROSPERO registration: CRD42020147415 (11/02/2020).

Fasting mimicking diets: A literature review of their impact on inflammatory arthritis

Fasting is an act of restricting, for a certain length of time, food intake or intake of particular foods, and has been part of religious rituals for centuries. Religions such as Christianity and Islam use this practice as a form of sacrifice, self-discipline, and gratitude. However, in the past decade, fasting has penetrated the mainstream as a diet trend. There are several ways of fasting; existing fast mimicking eating methods promise accelerated weight loss, and many more benefits: lower cholesterol, prevention of type 2 diabetes and a longer lifespan. Even more, it has been proposed that fasting can downregulate the inflammatory process and potentially be used as a treatment regimen for several diseases. Here, we review the effects of fasting on immune and inflammatory pathways. Also, we present current knowledge about the role of fasting in the activity of inflammatory arthritides with a focus on rheumatoid arthritis.

The effect of brief versus individually tailored dietary advice on change in diet, lipids and blood pressure in patients with inflammatory joint disease

BACKGROUND

Patients with inflammatory joint diseases (IJD) have an increased risk of cardiovascular disease (CVD) compared to the general population. Nutritional advice has been shown to influence CVD risk factors. Our objective was to evaluate whether an individually tailored dietary counselling versus a brief standardised advice on heart-friendly diet had comparable effect on change in diet, lipids and blood pressure (BP) in patients with IJD.

METHODS

Thirty-one patients with IJD aged 40-80 years received a brief standardised advice (4 min) on heart-friendly diet by a physician. Sixteen of the patients were randomised to receive an additional, individually tailored, heart-friendly dietary counselling session (60 min) by a dietitian. Change in dietary habits, measured by a validated questionnaire (SmartDiet), lipids, BP and C-reactive protein (CRP) were assessed after 8 weeks of follow-up.

RESULTS

After 8 weeks, the average increase in SmartDiet score was 5.1 and 5.7 points in the diet group (DG) and the control group (CG), respectively ( p = 0.65). Low-density lipoprotein cholesterol (LDL-c) was reduced by 12.6% in the DG versus 2.4% in the CG ( p = 0.05). There were no significant differences between the two groups regarding change in BP, lipids or CRP.

CONCLUSION

Individually tailored dietary counselling resulted in more heart-friendly food choices in patients with IJD. However, the change in SmartDiet score was comparable for IJD patients receiving a brief nutritional advice and individually tailored heart-friendly dietary counselling. Further studies evaluating the longitudinal effects of dietary advice on CVD outcome in patients with IJD are warranted.

Association between Bone Mineral Density of Femoral Neck and Geriatric Nutritional Risk Index in Rheumatoid Arthritis Patients Treated with Biological Disease-Modifying Anti-Rheumatic Drugs

Treatment of rheumatoid arthritis (RA) with biological disease-modifying anti-rheumatic drugs (bDMARDs) induces rapid remission. However, osteoporosis and its management remains a problem. The Geriatric Nutritional Risk Index (GNRI) evaluates the risk of malnutrition-related complications in elderly patients and has been shown to be a significant predictor of many diseases. We evaluated the correlation between GNRI and RA activity. In addition, risk factors for femoral neck bone loss were evaluated in RA patients treated with bDMARDs. We retrospectively examined the medical records of 146 patients with RA, collecting and recording the patients’ demographic and clinical characteristics. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. Inverse correlations were observed between GNRI and disease duration, disease activity score-28 joint count serum C-reactive protein (CRP), simple disease activity index, modified health assessment questionnaire score and CRP. GNRI showed correlation with femoral neck BMD and femoral neck BMD ≤ 70% of young adult men (YAM). Multiple regression analysis showed that female sex, increased age and lower GNRI were risk factors for lower BMD of the femoral neck. Multivariate binomial logistic regression analysis showed that female sex (odd ratio: 3.67) and lower GNRI (odd ratio: 0.87) were risk factors for BMD ≤ 70% of YAM. Because the GNRI is a simple method, it might be a simple predictor for RA activity and BMD status in RA patients. Complementary nutritional therapies might improve RA activity and osteoporosis in RA patients who have undergone treatment with bDMARDs.

Managing Rheumatoid Arthritis with Dietary Interventions

Self-help by means of dietary interventions can help in management of various disorders including rheumatoid arthritis (RA), a debilitating autoimmune disease. Dietary interventions necessitate a widespread appeal for both patients as well as clinicians due to factors including affordability, accessibility, and presence of scientific evidences that demonstrate substantial benefits in reducing disease symptoms such as pain, joint stiffness, swelling, tenderness and associated disability with disease progression. However, there is still an uncertainty among the community about the therapeutic benefits of dietary manipulations for RA. In the present review, we provide an account of different diets and their possible molecular mechanism of actions inducing observed therapeutic benefits for remission and management of RA. We further indicate food that can be a potential aggravating factor for the disease or may help in symptomatic relief. We thereafter summarize and thereby discuss various diets and food which help in reducing levels of inflammatory cytokines in RA patients that may play an effective role in management of RA following proper patient awareness. We thus would like to promote diet management as a tool that can both supplement and complement present treatment strategies for a better patient health and recovery.

Green tea and exercise interventions as nondrug remedies in geriatric patients with rheumatoid arthritis

This study aimed to evaluate the effects of green tea and supervised exercise training interventions on improvement of disease activity and bone metabolism markers in rheumatoid arthritis patients. [Subjects and Methods] One-hundred and twenty subjects who had a mean age of (60.7 ± 2.53 years) and had been diagnosed with rheumatoid arthritis at least ten years previously were randomly included in this study. Patients were treated with infliximab, green tea, or a supervised exercise program for six months. Disease activity markers as well as antioxidant activity of green tea extracts were estimated before supplementation using in vitro assays. [Results] Rheumatoid arthritis patients treated with green tea for 6 months alone or in combination with infliximab or an exercise program showed significant improvement in disease activity parameters, including C-reactive protein, and erythrocyte sedimentation rate, swollen and tender joints counts, and modified Stanford Health Assessment Questionnaire score, along with an increase in serum levels of bone resorption markers, i.e., deoxypyridinoline, amino-terminal telopeptide of type 1 collagen, and bone alkaline phosphatase, at 6 months of after initial treatment. The European League Against Rheumatism and American College of Rheumatology scores revealed more clinical improvement in the disease activity of rheumatoid arthritis patients treated with green tea along with exercise compared with rheumatoid arthritis patients treated with infliximab or exercise combinations. This may have been due to the higher potential antioxidant activity of green tea (89.6% to 96.5%). [Conclusion] Both exercise and green tea interventions appeared to be beneficial as nondrug modulates for rheumatoid arthritis disorders.

Effects of Dairy Products Consumption on Health: Benefits and Beliefs--A Commentary from the Belgian Bone Club and the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases

Dairy products provide a package of essential nutrients that is difficult to obtain in low-dairy or dairy-free diets, and for many people it is not possible to achieve recommended daily calcium intakes with a dairy-free diet. Despite the established benefits for bone health, some people avoid dairy in their diet due to beliefs that dairy may be detrimental to health, especially in those with weight management issues, lactose intolerance, osteoarthritis, rheumatoid arthritis, or trying to avoid cardiovascular disease. This review provides information for health professionals to enable them to help their patients make informed decisions about consuming dairy products as part of a balanced diet. There may be a weak association between dairy consumption and a possible small weight reduction, with decreases in fat mass and waist circumference and increases in lean body mass. Lactose intolerant individuals may not need to completely eliminate dairy products from their diet, as both yogurt and hard cheese are well tolerated. Among people with arthritis, there is no evidence for a benefit to avoid dairy consumption. Dairy products do not increase the risk of cardiovascular disease, particularly if low fat. Intake of up to three servings of dairy products per day appears to be safe and may confer a favourable benefit with regard to bone health.

Effects and mechanisms of vitamin A and vitamin E on the levels of serum leptin and other related cytokines in rats with rheumatoid arthritis

Leptin has been identified as an important cytokine in the inflammatory networks of rheumatoid arthritis (RA). Higher serum leptin levels may accelerate the development of RA. This study aimed to examine the effects of vitamin A (VitA) and vitamin E (VitE) on the levels of leptin and other related experimental and clinical indices, and to explore the mechanisms of these effects through the Janus kinase/signal transducer and activator of transcription (STAT) signal transduction pathway in rats with collagen-induced arthritis (CIA). CIA model rats were established by the intradermal injection of bovine type II collagen emulsified in incomplete Freund’s adjuvant, followed by a booster intradermal injection. Four weeks later, the CIA model rats were treated with 42.86 μg retinol equivalents/kg body weight (b.w.) VitA or 200 mg/kg b.w. VitE for four weeks. The levels of leptin, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-10, IL-4, C-reactive protein (CRP) and rheumatic factor were measured by ELISA using commercial kits, and the erythrocyte sedimentation rate (ESR) was determined. In addition, the expression levels of phosphorylated (p)-STAT1, p-STAT3 and leptin in the synovium were evaluated by western blot analysis. The results indicated that VitA and VitE significantly reduced the levels of leptin, TNF-α, IL-6 and CRP and the ESR and significantly increased the levels of IL-10 compared with those of the model group. Furthermore, significantly reduced p-STAT3 protein expression levels were observed in the VitA and VitE groups. In conclusion, VitA and VitE reduced the levels of serum leptin protein and other cytokines. Furthermore, VitA and VitE also reduced the p-STAT3 protein levels. The present study may provide a novel approach for the treatment of RA.

Nutritional status of Iranian women with rheumatoid arthritis: an assessment of dietary intake and disease activity

BACKGROUND

Long-standing chronic diseases such as rheumatoid arthritis are known to be associated with impairment of nutritional status to some degree. The present study aimed to assess nutritional status of women with rheumatoid arthritis and compare their ingestion of certain micronutrients with dietary reference intakes.

METHODS

In this cross-sectional study, 90 eligible women were recruited. After examination, all patients were evaluated on the basis of disease activity score, calculated using the number of tender and swollen joints, patient global assessment of pain and high sensitivity C-reactive protein (CRP). A three-day 24 h recall was completed and a 10 ml fasting blood sample was obtained to assess the plasma levels of malondialdehyde, total antioxidant and CRP.

RESULTS

Despite normal BMI, intake of energy and micronutrients including calcium, folic acid, zinc, magnesium and vitamin B6 were considerably lower compared with the dietary reference intakes. There was no significant relationship between intake of different nutrients or food groups and disease activity score and the biochemical markers including malondialdehyde, CRP and total antioxidant.

CONCLUSIONS

Intake of energy and some micronutrients were significantly lower than the recommended values. However, no relationship was found between intake of different food groups or nutrients with disease activity or serum antioxidant capacity.

Self-reported food intolerance and mucosal reactivity after rectal food protein challenge in patients with rheumatoid arthritis

OBJECTIVES

A dietary link to rheumatoid arthritis (RA) has been suspected and an influence on arthritic symptoms by different diets has been reported. Our primary aim was to record the self-experienced adverse food reactions in patients with RA. A secondary aim was to relate self-experienced adverse reactions to dairy produce and wheat to the local mucosal reactivity observed after rectal challenge with cow's milk protein (CM) and wheat gluten.

METHODS

A questionnaire about self-experienced adverse reaction to food was sent to 347 RA patients. Rectal challenge with CM and gluten was performed in 27 of these patients and in healthy controls (n = 18). After a 15-h challenge the mucosal production of nitric oxide (NO) and the mucosal release of myeloperoxidase (MPO) and eosinophil cationic protein (ECP) were measured by using the mucosal patch technique.

RESULTS

Twenty-seven per cent of the RA patients reported food intolerance (FI) to various foods, and in particular to CM, meat, and wheat gluten. Strong mucosal reactivity to CM was observed in 11% of the patients. Moderately increased mucosal reactivity to CM and gluten was found in 22% and 33%, respectively, of the patients. No relationship was found between self-experienced adverse reactions to CM or gluten and mucosal reactivity to these proteins.

CONCLUSIONS

Perceived FI is reported frequently by RA patients, with a prevalence similar to that reported previously in the general population. Mucosal reactivity to CM and gluten is seen in a minor fraction of RA patients and is not related to the frequently perceived intolerance to these proteins.

Rheumatoid cachexia is associated with dyslipidemia and low levels of atheroprotective natural antibodies against phosphorylcholine but not with dietary fat in patients with rheumatoid arthritis: a cross-sectional study

INTRODUCTION

Patients with rheumatoid arthritis (RA) have an increased risk for cardiovascular disease (CVD) independent of traditional risk factors. The aim of this study was to analyze the associations between diet, body composition, lipids and atheroprotective natural antibodies against phosphorylcholine (anti-PC) in patients with RA.

METHODS

A total of 80 RA patients (76% women), mean age (standard deviation (SD)) 61.4 (12) years and median disease duration of 6 years, were assessed by food frequency questionnaire (FFQ), fatty acid profile in adipose tissue and whole-body dual energy x ray absorptiometry (DXA). Rheumatoid cachexia was defined as fat free mass index below the 25th percentile and fat mass index above the 50th percentile of a reference population. Blood lipids, oxidized low-density lipoprotein (oxLDL) and anti-PC levels were determined.

RESULTS

The mean body mass index for the women and men was 25.0 and 27.0, respectively. Central obesity was found in 57% of the women (waist circumference >80 cm) and in 89% of the men (waist circumference >94 cm). In all, 18% of the women and 26% of the men had rheumatoid cachexia. These patients had significantly higher total cholesterol (P < 0.033), LDL (P < 0.029), and trendwise oxLDL (P = 0.056) as well as lower anti-PC IgM (P = 0.040), higher frequency of hypertension (69%) and metabolic syndrome (25%) than those without. The patients reported a high dietary intake of saturated fat, which partly correlated with fatty acid composition in adipose tissue and significantly with disease activity. However, patients with or without cachexia did not differ with respect to dietary fat intake or intake of Mediterranean-like diet. Additionally, patients on a Mediterranean-like diet had high levels of anti-PC (P < 0.001).

CONCLUSIONS

About one in five patients with low-active RA displayed rheumatoid cachexia. This condition was associated with high levels of LDL cholesterol, low levels of atheroprotective anti-PC and high frequency of hypertension, which is of interest in the context of CVD in RA. The cachexia could not be related to diet fat intake. However, patients on a Mediterranean-like diet had high anti-PC levels in spite of similar frequency of cachexia. High anti-PC levels may provide some protection against CVD.

Use of herbs among adults based on evidence-based indications: findings from the National Health Interview Survey

OBJECTIVE

To examine the extent to which US adults use herbs (herbal supplements) in accordance with evidence-based indications.

PATIENTS AND METHODS

The Alternative Health supplement of the 2002 National Health Interview Survey (NHIS) is part of an annual, nationally representative survey of US adults. It contains data on adults' use of the 10 herbs most commonly taken to treat a specific health condition in the past year (January 1 to December 31, 2002). The Natural Standard database was used to formulate evidence-based standards for herb use. These standards were applied to the NHIS data to identify groups of people who used herbs appropriately and inappropriately, using a multivariable logistic regression model.

RESULTS

Of the 30,617 adults surveyed, 5787 (18.9%) consumed herbs in the past 12 months; of those, 3315 (57.3%) used herbs to treat a specific health condition. Among people who used only 1 herb (except echinacea and ginseng), approximately one third used it consonant with evidence-based indications. Women and people with a college education were more likely to use herbs (with the exception of echinacea) concordant with scientific evidence. Adults younger than 60 years and black adults were significantly less likely to use herbs (with the exception of echinacea) based on evidentiary referents than their counterparts. However, for echinacea users, no significant differences were detected.

CONCLUSION

Roughly two thirds of adults using commonly consumed herbs (except echinacea) did not do so in accordance with evidence-based indications. Health care professionals should take a proactive role, and public health policies should disseminate evidence-based information regarding consumption of herbal products.

Antioxidants and coronary artery disease among individuals with type 1 diabetes: Findings from the Pittsburgh Epidemiology of Diabetes Complications Study

OBJECTIVE

Oxidative stress has been implicated in the development of diabetes and cardiovascular disease. We evaluated the effect of serum antioxidants and total antioxidant reserve (TAR) on coronary artery disease (CAD) incidence in type 1 diabetes.

METHODS

Subjects were identified from the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) cohort, a 10-year prospective study of childhood-onset type 1 diabetes. Mean age at baseline was 28 and diabetes duration 19 years. Coronary artery disease was defined as physician-diagnosed angina, confirmed MI, stenosis >or=50%, ischemic electrocardiogram (ECG), or revascularization. Controls were gender, age, and diabetes duration (+/-3 years) matched with cases. Samples and risk factors used in analyses were identified from the earliest exam prior to incidence in cases (54 cases, 67 controls).

RESULTS

None of the antioxidant measures (alpha-tocopherol, gamma-tocopherol, retinol, TAR) showed protection against incident CAD overall. However, a protective effect of alpha-tocopherol against CAD was observed among antioxidant supplement users (HR=0.22, 95% CI=0.10-0.49) and in renal disease (HR=0.46, 95% CI=0.23-0.91). Despite similar alpha-tocopherol concentration, there was no protective effect among nonusers of antioxidant supplements.

CONCLUSIONS

High alpha-tocopherol levels among patients with renal disease and in those using vitamin supplements were associated with lower CAD risk in type 1 diabetes. The specificity of these effects merits further investigation.

Anti-inflammatory and anti-arthritic effects of Yucca schidigera: a review

Yucca schidigera is a medicinal plant native to Mexico. According to folk medicine, yucca extracts have anti-arthritic and anti-inflammatory effects. The plant contains several physiologically active phytochemicals. It is a rich source of steroidal saponins, and is used commercially as a saponin source. Saponins have diverse biological effects, including anti-protozoal activity. It has been postulated that saponins may have anti-arthritic properties by suppressing intestinal protozoa which may have a role in joint inflammation. Yucca is also a rich source of polyphenolics, including resveratrol and a number of other stilbenes (yuccaols A, B, C, D and E). These phenolics have anti-inflammatory activity. They are inhibitors of the nuclear transcription factor NFkappaB. NFkB stimulates synthesis of inducible nitric oxide synthase (iNOS), which causes formation of the inflammatory agent nitric oxide. Yucca phenolics are also anti-oxidants and free-radical scavengers, which may aid in suppressing reactive oxygen species that stimulate inflammatory responses. Based on these findings, further studies on the anti-arthritic effects of Yucca schidigera are warranted.

Diet and rheumatoid arthritis: a review of the literature

INTRODUCTION

Rheumatoid arthritis is a common inflammatory condition. A large number of patients seek alternative or complementary therapies of which diet is an important component. This article reviews the evidence for diet in rheumatoid arthritis along with the associated concept of oral tolerization.

METHODS

References were taken from Medline from 1966 to September 2004. The keywords, rheumatoid arthritis, diet, n-3 fatty acids, vitamins, and oral tolerization, were used.

RESULTS

Randomized controlled trials (RCTs) indicate that dietary supplementation with n-3 fatty acids provides modest symptomatic benefit in groups of patients with rheumatoid arthritis. Epidemiological studies and RCTs show cardiovascular benefits in the broader population and patients with ischemic heart disease. A number of mechanisms through which n-3 fats may reduce inflammation have been identified. In a small number of patients with rheumatoid arthritis, other dietary manipulation such as fasting, vegan, and elimination diets may have some benefit. However, many of these diets are impractical or difficult to sustain long term.

CONCLUSIONS

Dietary manipulation provides a means by which patients can a regain a sense of control over their disease. Dietary n-3 supplementation is practical and can be easily achieved with encapsulated or, less expensively, bottled fish oil.

Nutritional management of rheumatoid arthritis: a review of the evidence

Rheumatoid arthritis (RA) is a debilitating disease and is associated with increased risk of cardiovascular disease and osteoporosis. Poor nutrient status in RA patients has been reported and some drug therapies, such as nonsteroidal anti-inflammatory drugs (NSAIDs), prescribed to alleviate RA symptoms, may increase the requirement for some nutrients and reduce their absorption. This paper reviews the scientific evidence for the role of diet and nutrient supplementation in the management of RA, by alleviating symptoms, decreasing progression of the disease or by reducing the reliance on, or combating the side-effects of, NSAIDs. Supplementation with long-chain n-3 polyunsaturated fatty acids (PUFA) consistently demonstrates an improvement in symptoms and a reduction in NSAID usage. Evidence relating to other fatty acids, antioxidants, zinc, iron, folate, other B vitamins, calcium, vitamin D and fluoride are also considered. The present evidence suggests that RA patients should consume a balanced diet rich in long-chain n-3 PUFA and antioxidants. More randomized long-term studies are needed to provide evidence for the benefits of specific nutritional supplementation and to determine optimum intake, particularly for n-3 PUFA and antioxidants.

Dietary supplement use and medical conditions: the VITAL study

BACKGROUND

Over half of U.S. adults use vitamin or mineral supplements, and some are likely using supplements to treat chronic diseases or risk factors for disease. Information on the relationship between supplement use and medical conditions is useful to health professionals to understand the self-medication behavior of their patients, and important for researchers because medical conditions may be potential confounding factors in observational studies of supplement use and disease risk.

METHODS

The cross-sectional data in this report are from 45,748 participants, aged 50 to 75 years, who completed a self-administered, mailed questionnaire on current dietary supplement use (multivitamins plus 16 individual vitamins or minerals), medical history (cancer, cardiovascular-related diseases, and other self-reported medical conditions), and demographic characteristics.

RESULTS

Supplement use (mean number used at least once a week) was higher among respondents who were older, female, highly educated, Caucasian, and of normal body mass index (all p<0.001). After controlling for these covariates, supplement use was higher among those with the condition for 13 of the 21 conditions examined (p<0.01); only having diabetes or high stress was associated with using fewer supplements. For specific supplements, the strongest associations were for cardiovascular disease and its risk factors with vitamin E, niacin, and folate, and for calcium with indigestion and acid reflux disease. For several conditions, the relative odds of using specific supplements were consistently higher for men than for women.

CONCLUSIONS

Supplement use was associated with many medical conditions in this cohort. However, these cross-sectional data do not permit inferences about the temporal sequence. Some associations appeared to be based on evidence for efficacy (e.g., folate with coronary artery disease), and others could be based on misinformation (e.g., selenium with benign prostatic hyperplasia).

Breastfeeding-related onset, flare, and relapse of rheumatoid arthritis

The beneficial effects of pregnancy on rheumatoid arthritis have been known for decades. Only recently, however, have lactation and prolactin been targeted as predictors of onset, flare, or relapse of arthritis. Among genetically susceptible women, breastfeeding is associated with an increased risk of rheumatoid arthritis, particularly after the first pregnancy. Dietary interventions may reduce symptoms experienced by arthritic women.

Internal locus of control and social support associated with some dietary changes by elderly participants in a diet intervention trial

OBJECTIVE

Measure relationships of locus of control and social support to diet changes in an intervention trial.

DESIGN

Participants in the Polyp Prevention Trial (PPT) completed Multidimensional Health Locus of Control (MHLC) and Norbeck Social Support Questionnaires (NSSQ) and modified Block food frequency questionnaires. Data were collected at baseline and 1 year later.

SUBJECTS/SETTING

A convenience sample of PPT intervention (N = 68) and control (n = 43) participants at 1 clinical center participated in this ancillary study.

MAIN OUTCOME MEASURES

Mean daily dietary intakes after 1 year were compared with baseline values. Intervention participants' scores for MHLC internal locus of control and NSSQ total functional network were correlated with diet changes.

STATISTICAL ANALYSES PERFORMED

Group percentages were compared using the Fisher exact test; means were compared by t test.

RESULTS

Groups were comparable in demographics, baseline diet, and scores for internal locus of control and total functional network. Intervention group participants made greater diet changes than control participants in intake of fat (-27 g vs -8 g), fat as a percentage of kilocalories (-8% vs -2%), fiber as grams per 1,000 kcal (7 g vs 0.3 g), and daily fruit/vegetable servings (2.0 vs 0.2). Pearson correlations of diet changes with internal locus of control scores (all P > .05) were fat grams, r = 0.031; fat as percentage of kilocalories, r = 0.023; fiber grams per 1,000 kcal; r = 0.230; and fruit/vegetable servings, r = 0.186. Correlations with total functional network scores were: fat grams, r = 0.022 (P > .05); fat as percentage of kilocalories, r = -0.108 (P > .05); fiber grams per 1,000 kcal, r = 0.276, P < .05; and daily fruit/vegetable servings, r = 0.326, P < .05.

APPLICATIONS/CONCLUSIONS

Intensive and skillful dietary intervention can succeed whether or not clients bring strong internal locus of control or social support to the diet change program.