Weight Loss, the Obesity Paradox, and the Risk of Death in Rheumatoid Arthritis

Cardiovascular outcomes of patients with rheumatoid arthritis prescribed disease modifying anti-rheumatic drugs: a review

INTRODUCTION

Rheumatoid arthritis (RA) is associated with a heightened risk of cardiovascular disease (CVD), with both traditional CV risk factors and inflammation contributing to this risk.

AREAS COVERED

This review highlights the burden of CVD in RA and associated traditional CV risk factors, including the complexity of dyslipidemia in RA and the so-called 'lipid paradox.' Furthermore, the recognized RA-disease-specific factors associated with higher risk of CVD and the role of systemic inflammation in the pathogenesis of CVD in RA will be addressed. With the advent of biologic and targeted synthetic therapies in the treatment of RA, the effect of conventional and newer generation disease modifying anti-rheumatic therapies (DMARDs) on CV risk and associated risk factors will also be discussed.

EXPERT OPINION

Identifying the RA phenotype at greatest risk of CVD, understanding the interplay of increased traditional risk factors, common inflammatory processes and RA-specific factors, and personalized use of DMARDs according to disease phenotype and comorbidity to reduce this risk are key areas for future research.

Increased cardiovascular risk in rheumatoid arthritis: mechanisms and implications

Rheumatoid arthritis is a systemic autoimmune disease characterized by excess morbidity and mortality from cardiovascular disease. Mechanisms linking rheumatoid arthritis and cardiovascular disease include shared inflammatory mediators, post-translational modifications of peptides/proteins and subsequent immune responses, alterations in the composition and function of lipoproteins, increased oxidative stress, and endothelial dysfunction. Despite a growing understanding of these mechanisms and their complex interplay with conventional cardiovascular risk factors, optimal approaches of risk stratification, prevention, and treatment in the context of rheumatoid arthritis remain unknown. A multifaceted approach to reduce the burden posed by cardiovascular disease requires optimal management of traditional risk factors in addition to those intrinsic to rheumatoid arthritis such as increased disease activity. Treatments for rheumatoid arthritis seem to exert differential effects on cardiovascular risk as well as the mechanisms linking these conditions. More research is needed to establish whether preferential rheumatoid arthritis therapies exist in terms of prevention of cardiovascular disease. Ultimately, understanding the unique mechanisms for cardiovascular disease in rheumatoid arthritis will aid in risk stratification and the identification of novel targets for meaningful reduction of cardiovascular risk in this patient population.

Association of weight loss with improved disease activity in patients with rheumatoid arthritis: A retrospective analysis using electronic medical record data

Objective

To evaluate the association between weight loss and rheumatoid arthritis (RA) disease activity.

Methods

We conducted a retrospective cohort study of RA patients seen at routine clinic visits at an academic medical center, 2012-2015. We included patients who had ≥2 clinical disease activity index (CDAI) measures. We identified visits during follow-up where the maximum and minimum weights occurred and defined weight change and CDAI change as the differences of these measures at these visits. We defined disease activity improvement as CDAI decrease of ≥5 and clinically relevant weight loss as ≥5 kg. We performed logistic regression analyses to establish the association between improved disease activity and weight loss and baseline BMI category (≥25 kg/m² or <25 kg/m²). We built linear regression models to investigate the association between continuous weight loss and CDAI change among patients who were overweight/obese at baseline and who lost weight during follow-up.

Results

We analyzed data from 174 RA patients with a median follow-up of 1.9 years (IQR 1.3-2.4); 117 (67%) were overweight/obese at baseline, and 53 (31%) lost ≥5 kg during follow-up. Patients who were overweight/obese and lost ≥5 kg had three-fold increased odds of disease activity improvement compared to those who did not (OR 3.03, 95%CI 1.18-7.83). Among those who were overweight/obese at baseline, each kilogram weight loss was associated with CDAI improvement of 1.15 (95%CI 0.42-1.88). Our study was limited by using clinical data from a single center without fixed intervals for assessments.

Conclusion

Clinically relevant weight loss (≥5 kg) was associated with improved RA disease activity in the routine clinical setting. Further studies are needed for replication and to evaluate the effect of prospective weight loss interventions on RA disease activity.

Body Mass Index, Weight Loss, and Cause-Specific Mortality in Rheumatoid Arthritis

OBJECTIVE

To examine associations of body mass index (BMI) and weight loss with cause-specific mortality in rheumatoid arthritis (RA).

METHODS

A cohort of US veterans with RA was followed until death or through 2013. BMI was categorized as underweight, normal, overweight, and obese. Weight loss was calculated as the 1) annualized rate of change over the preceding 13 months, and 2) cumulative percent. Vital status and cause of death were obtained from the National Death Index. Multivariable competing-risks regression models were utilized to assess the time-varying associations of BMI and weight loss with cause-specific mortality.

RESULTS

Among 1,600 participants and 5,789 patient-years of followup, 303 deaths occurred (95 cardiovascular, 74 cancer, and 46 respiratory). The highest weight-loss rate and weight-loss percent were associated with a higher risk of cardiovascular mortality (rate: subdistribution hazard ratio [sHR] 2.27 [95% confidence interval (95% CI) 1.61-3.19]; percent: sHR 2.31 [95% CI 1.06-5.01]) and cancer mortality (rate: sHR 2.36 [95% CI 1.11-5.01]; percent: sHR 1.90 [95% CI 1.00-3.62]). Overweight BMI was protective of cardiovascular mortality (sHR 0.59 [95% CI 0.38-0.91]), while underweight BMI was associated with a near 3-fold increased risk of respiratory mortality (sHR 2.93 [95% CI 1.28-6.67]). Incorporation of time-varying BMI and weight loss in the same models did not substantially alter individual associations for cardiovascular and cancer mortality, but an association between weight-loss percentage and respiratory mortality was attenuated after BMI adjustment.

CONCLUSION

Both BMI and weight loss are predictors of cause-specific mortality in RA. Weight loss is a strong predictor of cardiovascular and cancer mortality, while underweight BMI is a stronger predictor of respiratory mortality.

Weight Change During the Early Rheumatoid Arthritis Period and Risk of Subsequent Mortality in Women With Rheumatoid Arthritis and Matched Comparators

OBJECTIVE

To investigate whether weight change during the early rheumatoid arthritis (RA) period is associated with subsequent mortality and to evaluate whether there is an RA-specific effect.

METHODS

We identified patients with incident RA during the Nurses' Health Study (NHS; 1976-2016) and created a comparison cohort by matching each RA patient with up to 10 non-RA comparators by age and calendar year of the RA diagnosis (index date). To capture weight change around the early RA period ("peri-RA/index"), we used weight measurements collected 2-4 years before and 2-4 years after the index date. We used Cox regression analysis to estimate hazard ratios (HRs) for mortality according to peri-RA/index weight change categories, separately in each cohort and in the combined cohorts, evaluating for an RA-specific effect.

RESULTS

Among 121,701 women in the NHS, 902 patients with incident RA were identified and matched to 7,884 non-RA comparators. In the RA cohort, 371 deaths (41.1%) occurred during a mean follow-up of 17.0 years after the early RA period, and 2,303 deaths (29.2%) occurred in the comparison cohort during a mean follow-up of 18.4 years. Weight loss of >30 pounds during the peri-RA period had a hazard ratio (HR) for mortality of 2.78 (95% confidence interval [95% CI] 1.58-4.89) compared to stable weight; results in the comparison cohort were similar (HR 2.16, 95% CI 1.61-2.88). A weight gain of >30 pounds had no association with mortality in patients with RA (HR 1.45, 95% CI 0.69-3.07) or comparators (HR 1.19, 95% CI 0.89-1.59). For mortality, there was no statistically significant interaction between RA/comparator status and weight change category (P = 0.68).

CONCLUSION

Severe weight loss during the early RA period was associated with an increased subsequent mortality risk for women with and those without RA. These results extend prior observations by including non-RA comparators and finding no protective association between weight gain and mortality, providing evidence against an RA-specific obesity paradox for mortality.

Aging, Obesity, and Inflammatory Age-Related Diseases

The increase in the prevalence of obesity represents a worldwide phenomenon in all age groups and is pathologically and genetically correlated with several metabolic and cardiovascular diseases, representing the most frequent age-related diseases. Obesity superimposed on aging drastically increases chronic low-grade inflammation (inflammaging), which is an important link between obesity, insulin resistance, and age-associated diseases. Immune cells of both the innate and the adaptive immune systems infiltrate the adipose tissue (AT) and during obesity induce inflammatory responses associated with metabolic switches and changes in phenotypes and function of immune cell subsets. Obesity poses new health problems especially when it occurs in the context of other diseases, many of them frequently affect elderly subjects. An emerging problem is the decreased proportion of patients with obesity achieving clinical response to therapy. In this review, we will discuss the reciprocal influences of immune cell and AT inflammation in aging and age-associated diseases and the complex relationship of nutrient and energy-sensing homeostatic checkpoints, which contribute to shape the phenotype of the AT. We will specifically examine type-2 diabetes, rheumatoid arthritis, osteoarthritis, cognitive impairment, and dementia, where obesity plays a significant role, also in shaping some clinical aspects.

Impact of Obesity and Adiposity on Inflammatory Markers in Patients With Rheumatoid Arthritis

OBJECTIVE

The C-reactive protein (CRP) level and erythrocyte sedimentation rate (ESR) are important disease activity biomarkers in rheumatoid arthritis (RA). This study aimed to determine to what extent obesity biases these biomarkers.

METHODS

Body mass index (BMI) associations with CRP level and ESR were assessed in 2 RA cohorts: the cross-sectional Body Composition (BC) cohort (n = 451), including whole-body dual x-ray absorptiometry measures of fat mass index; and the longitudinal Veterans Affairs Rheumatoid Arthritis (VARA) registry (n = 1,652), using multivariable models stratified by sex. For comparison, associations were evaluated in the general population using the National Health and Nutrition Examination Survey.

RESULTS

Among women with RA and in the general population, greater BMI was associated with greater CRP levels, especially among women with severe obesity (P < 0.001 for BMI ≥35 kg/m2 versus 20-25 kg/m2 ). This association remained after adjustment for joint counts and patient global health scores (P < 0.001 in BC and P < 0.01 in VARA), but was attenuated after adjustment for fat mass index (P = 0.17). Positive associations between BMI and ESR in women were more modest. In men with RA, lower BMI was associated with higher CRP levels and ESR, contrasting with positive associations among men in the general population.

CONCLUSION

Obesity is associated with higher CRP levels and ESR in women with RA. This association is related to fat mass and not RA disease activity. Low BMI is associated with higher CRP levels in men with RA; this unexpected finding remains incompletely explained but likely is not a direct effect of adiposity.

Prevalence of rheumatoid cachexia assessed by bioelectrical impedance vector analysis and its relation with physical function

Rheumatoid arthritis (RA) patients frequently have changes in their body composition, with a decrease in muscle mass and an increase in fat mass, a syndrome that is termed rheumatoid cachexia (RC). The prevalence of this nutritional alteration is not well known; there is as yet no consensus, seeing as it depends on the methods, techniques, and cutoff points that are used for its diagnosis. The main aim of this study was to identify RC through assessment by bioelectrical impedance vector analysis (BIVA) and its association with metabolic causes, physical function, and the main disease status, among others. The prevalence of RC was identified in those subjects who fell outside the right lower quadrant of the reference curve of RXc graph of BIVA. Clinical, anthropometric, biochemical and physical activity, emotional status, and diet markers were also evaluated. Ninety-four patients were included (92.55% women). The prevalence of RC assessed by BIVA was 21.28%. BIVA-cachexia patients had a lesser value of handgrip strength vs. patients without BIVA-cachexia 10.2 kg (7.2-13.4) vs. 14.7 kg (9.6-19), p = 0.0062. Disability and folic acid with methotrexate consumption are related to BIVA-cachexia ((OR 4.69, 95% CI 1.33, 16.54, p = 0.016) and (OR 0.19, 95%CI 0.058, 0.651, p = 0.008), respectively). BIVA could represent a valuable tool to assess presence of RC. It is important that RA patients have physical therapy to improve their nutritional status.

Association Between Obesity and Migraine in Women

PURPOSE OF REVIEW

Migraine is a common and highly disabling condition that is particularly prevalent among women and especially women of reproductive age. The tremendous rise in adiposity in the Western world has led to an epidemic of obesity in women. The particular effects of obesity on women with migraine of various ages are the focus of this review.

RECENT FINDINGS

Conflicting findings from various studies with different approaches and populations have made challenging definitive conclusions about associations between migraine and obesity. While the association between obesity and migraine frequency has been consistently demonstrated and obesity is considered a risk factor for progression from episodic to chronic migraine, the association between obesity and migraine prevalence is still somewhat debated and appears to be dependent on gender and age, with the most consistent effects observed in women younger than 55 years of age. Association between migraine and obesity is most commonly observed in women of reproductive age. The multimodal changes associated with age and hormonal change in women likely play a role in this relationship, as obesity does not appear to be related to migraine in women over 55 years of age. Future studies focusing on the migraine-obesity relationship in women should examine the effects of age, endogenous hormonal state, and exogenous hormones on migraine and obesity.

Changes in Body Mass Related to the Initiation of Disease-Modifying Therapies in Rheumatoid Arthritis

OBJECTIVE

Unintentional weight loss is important and can be predictive of long-term outcomes in patients with rheumatoid arthritis (RA). This study was undertaken to assess how primary therapies for RA may influence changes in body mass index (BMI) in RA patients from a large administrative database.

METHODS

Unique dispensing episodes of methotrexate, prednisone, leflunomide, and tumor necrosis factor inhibitors (TNFi) administered to RA patients were identified from the US Department of Veterans Affairs pharmacy databases. Values for C-reactive protein (CRP) level and BMI closest to the time point within 30 days of the treatment course start date and at follow-up time points were linked. Missing laboratory values were imputed. Weight loss was defined as a decrease in BMI of >1 kg/m(2) . Regression models were used to evaluate changes in BMI during each drug treatment as compared to treatment with methotrexate. To assess the impact of confounding by indication, propensity scores for use of each drug were incorporated in analyses using matched-weighting techniques.

RESULTS

In total, 52,662 treatment courses in 32,859 RA patients were identified. At 6 months from the date of prescription fill, weight gain was seen among patients taking methotrexate, those taking prednisone, and those taking TNFi. On average, compared to methotrexate-treated patients, prednisone-treated patients had significantly more weight gain, while leflunomide-treated patients demonstrated weight loss. In multivariable models, more weight loss (β = -0.41 kg/m(2) , 95% confidence interval [95% CI] -0.46, -0.36; P < 0.001) and a greater risk of weight loss (odds ratio 1.73, 95% CI 1.55, 1.79; P < 0.001) were evident among those receiving leflunomide compared to those receiving methotrexate. Treatment with prednisone was associated with greater weight gain (β = 0.072 kg/m(2) , 95% CI 0.042, 0.10; P < 0.001). These associations persisted in analyses adjusted for propensity scores and in sensitivity analyses.

CONCLUSION

Leflunomide is associated with significantly more, but modest, weight loss, while prednisone is associated with greater weight gain compared to other therapies for RA.

Investigation Of Obesity-Related Mortality Rates In Delaware

As Delaware's adult obesity crisis continues to be a leading public health concern, we evaluated Delaware's 1999-2014 vital records to examine the association between obesity and mortality. We used the Delaware population death records from the Centers for Disease Control and Prevention (CDC) WONDER database and the Delaware Health Statistics Center (DHSC). Together with the vital records, we incorporated Microsoft Excel, SAS (Statistical Analysis System) and GIS (geographic information system) tools to analyze obesity influences from county residence, economic status, education, gender, and race. Using the 15-year (1999-2014) time span with the CDC WONDER database, we observed a statistically significant 28.7% increase in the age-adjusted Delaware obesity-related mortality rates (where obesity was a contributory factor). Furthermore, obesity influenced death counts in all three Delaware counties (New Castle, Kent, and Sussex). Kent County experienced the largest increase (66.0%), followed by New Castle County (47.4%), and Sussex County (25.2%). The DHSC mortality rates for all leading causes of death from 2000 to 2011 indicated relatively stable mortality rates for Delaware. However, using CDC WONDER data, the Delaware mortality rate for obesity as a single underlying cause in 2011 was 56.9% higher than mortality rate in 2000.

Obesity paradox and mortality in adults with and without incident type 2 diabetes: a matched population-level cohort study

OBJECTIVE

Among adults with type 2 diabetes (T2D), several (but not all) studies show that being overweight (body mass index (BMI): 25.0-29.9 kg/m2) or obese I (BMI: 30.0-34.9 kg/m2) near the time of diagnosis, is unexpectedly associated with reduced all-cause mortality compared with normal weight-the obesity paradox. We addressed whether this observation is causal (eg, a true protective effect); due to confounding (including effect modification); or due to selection ('collider') bias.

RESEARCH DESIGN AND METHODS

We performed a matched population-level cohort study using primary care records from Salford, UK (1995-2012) in 10 464 patients with incident T2D paired (1:3) with 31 020 individuals who never developed T2D. We estimated HRs for associations of BMI with all-cause mortality using Cox models, stratified by smoking status.

RESULTS

Median follow-up was 8.7 years. For never smokers, the hazard of all-cause mortality increased from 25 kg/m2, in a linear manner, with increasing BMI in the T2D cohort (HR per 5 kg/m2: 1.23, ptrend<0.001) and in the non-diabetes cohort (HR per 5 kg/m2: 1.34, ptrend<0.001). In contrast, among ever smokers, BMI-mortality relationships were U-shaped in the T2D and non-diabetes cohorts. Evidence of the obesity paradox in ever smokers, with and without T2D, argued against a selection bias, but supported a contribution of effect modification by smoking (pinteraction=0.009). Results were stable to various sensitivity analyses.

CONCLUSIONS

In this cohort, the obesity paradox is mainly explained by smoking as an effect modifier. These findings indicate that the obesity paradox does not challenge standard weight management recommendations among T2D patients.

Methods Employed to Assess Weight Loss in Older Adults by Means of Electronic Medical Records: A Systematic Review

Electronic medical records (EMRs) can be used to identify and categorize weight loss in older adults, but research has not scrutinized methods for doing so. Through a modified PRISMA protocol, we systematically reviewed published methods for quantifying weight change from EMRs. Articles (all available through July 2016) were identified through PubMed and SCOPUS searches, screened, and evaluated. We abstracted relevant data and tabulated the methods to assess weight change. The 13 selected articles showed little consistency in the approach to key methodological issues: 1) time ranges assessed; 2) removal of spurious values; 3) metrics to quantify weight change; 4) number of measures needed to estimate change; 5) threshold for significant weight change; and 6) relation to ideal weight. There was essentially no consensus around how to identify and categorize weight loss. Further investigation is needed to establish scientifically validated and clinically useful algorithms, accounting for the six issues above.

Impact of Obesity on Remission and Disease Activity in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

To summarize the relationship between obesity and remission in rheumatoid arthritis (RA); secondary objectives were to summarize other measures of treatment response and mortality in RA.

METHODS

Medline and Embase searches were performed in March 2016 using relevant MeSH and keyword terms for obesity and RA. Articles were selected if they reported estimates for achieving remission in obese subjects relative to other body mass index (BMI) categories, or changes in composite or individual disease activity measures or patient-reported outcomes during therapy, or mortality rates, in relation to BMI category or on a continuous scale. Remission outcomes were conducive to meta-analysis, and all other outcomes were summarized.

RESULTS

A total of 3,368 records were screened; we included 8 reporting remission rates, 9 reporting disease activity measures or patient-reported outcomes, and 3 examining mortality by obesity status or BMI. Obese patients attain remission less frequently than nonobese and/or normal-weight patients. In adjusted models, obese patients demonstrated lower odds of achieving remission (pooled odds ratio [OR] 0.57 [95% confidence interval (95% CI) 0.45, 0.72]) and sustained remission (pooled OR 0.49 [95% CI 0.32, 0.74]) relative to nonobese subjects. Most studies found obese patients to have worse Disease Activity Scores or Disease Activity Scores in 28 joints, tender joint counts, inflammatory markers, patient global evaluation scores, pain scores, and physical function scores during followup, but not worse swollen joint counts. Obesity was not associated with increased mortality.

CONCLUSION

Obesity decreases the odds of achieving remission in RA and negatively impacts disease activity and patient-reported outcomes during therapy. Interventions to reduce BMI should be investigated for their ability to improve disease outcomes.

The Obesity Epidemic and Consequences for Rheumatoid Arthritis Care

With the prevalence of obesity increasing dramatically worldwide over the past several decades, an increasing body of literature has examined the impact of obesity in the context of rheumatoid arthritis (RA). Epidemiologic studies suggest that obesity may be associated with a modestly increased risk for the development of RA, although these studies have shown conflicting results. Among patients with established RA, obesity has been observed to be associated with greater subjective measures of disease activity and poor treatment response, but also with a decreased risk of joint damage and lower mortality. A comprehensive evaluation of the influence of obesity on the measurement of disease, response to therapies, and long-term prognosis is critical in order to understand these observations. This review therefore focuses on recent observations, potential explanations for these findings, and implications for clinicians and investigators caring for and studying patients with RA.

Managing cardiovascular risk in patients with inflammatory arthritis: practical considerations

Patients with inflammatory arthritis, such as rheumatoid arthritis, psoriatic arthritis, or ankylosing spondylitis, have higher rates of cardiovascular mortality. While the increased cardiovascular risk is only explained to some extent, a lot of research is currently conducted to improve our understanding of its pathogenesis, risk stratification, and optimal cardiovascular risk management. This review sought to report epidemiological data pertaining to the cardiovascular disease burden in patients with inflammatory arthritis, underlying mechanisms accounting for excessive cardiovascular risk, along with recommendations regarding risk assessment and management in this patient population.

Insight into rheumatological cause and effect through the use of Mendelian randomization

Establishing causality of risk factors is important to determine the pathogenetic mechanisms underlying rheumatic diseases, and can facilitate the design of interventions to improve care for affected patients. The presence of unmeasured confounders, as well as reverse causation, is a challenge to the assignment of causality in observational studies. Alleles for genetic variants are randomly inherited at meiosis. Mendelian randomization analysis uses these genetic variants to test whether a particular risk factor is causal for a disease outcome. In this Review of the Mendelian randomization technique, we discuss published results and potential applications in rheumatology, as well as the general clinical utility and limitations of the approach.

Biomolecular features of inflammation in obese rheumatoid arthritis patients: management considerations

Adipose tissue is an active organ playing a role not only in metabolism but also in immune and inflammatory processes, releasing several pro-inflammatory mediators. This can explain the possible association between obesity and rheumatoid arthritis (RA) and its role in the progression of the disease. Adipose and synovial tissues share common histological features of local inflammation in terms of activation of target tissues infiltrating cells (i.e. myeloid cells). Among the so-called adipocytokines, PEDF and Chemerin orchestrate the cellular cross-talk between adipose and myeloid cells, being possible biomarkers to monitor the effect of weight loss or the decrease of adipose tissue in patients with RA. Moreover, dietary intervention has been demonstrated to reduce Chemerin as well as IL-6 and MCP-1 expression. Finally, epigenetic regulators such as micro-RNAs (i.e. miR-155) are key regulators of myeloid cells activation in RA and obesity as well as in adipocytes. In this review, we will summarize the biological link between obesity/overweight state and RA focusing on pathophysiological mechanisms, consequences and management considerations.

Body composition phenotypes and obesity paradox

PURPOSE OF REVIEW

The obesity paradox is a highly controversial concept that may be attributed to methodological limitations related to its identification. One of the primary concerns is the use of BMI to define obesity. This index does not differentiate lean versus adipose tissue compartments (i.e. body composition) confounding health consequences for morbidity and mortality, especially in clinical populations. This review will describe the past year's evidence on the obesity paradox phenomenon, primarily focusing on the role of abnormal body composition phenotypes in explaining the controversies observed in the literature.

RECENT FINDINGS

In spite of the substantial number of articles investigating the obesity paradox phenomenon, less than 10% used a direct measure of body composition and when included, it was not fully explored (only adipose tissue compartment evaluated). When lean tissue or muscle mass is taken into account, the general finding is that a high BMI has no protective effect in the presence of low muscle mass and that it is the latter that associates with poor prognosis.

SUMMARY

In view of the body composition variability of patients with identical BMI, it is unreasonable to rely solely on this index to identify obesity. The consequences of a potential insubstantial obesity paradox are mixed messages related to patient-related prognostication.