Rheumatoid arthritis and mortality. A longitudinal study in Pima Indians.

National Institute of Arthritis and Musculoskeletal and Skin Diseases, Phoenix, Arizona.
Arthritis & Rheumatology (Impact Factor: 7.87). 08/1993; 36(8):1045-53. DOI: 10.1002/art.1780360804
Source: PubMed

ABSTRACT To determine the effect of rheumatoid arthritis (RA) on mortality rates.
Longitudinal analyses of data from a cohort of Pima Indians from the Gila River Indian Community in Arizona, who were followed up during the period February 1965 through December 1989.
Among 2,979 study subjects aged > or = 25 years, there were 858 deaths, 79 of which occurred in subjects with RA (36 men, 43 women). Age- and sex-adjusted mortality rates were slightly higher in subjects with RA than in those without (mortality rate ratio 1.28, 95% confidence interval [95% CI] 1.01-1.62). Among those with RA, mortality rates were higher in older subjects (mortality rate ratio 1.51 per 10-year increase in age, 95% CI 1.22-1.88), in male subjects (mortality rate ratio 2.23, 95% CI 1.44-3.45, adjusted for age), and in subjects with proteinuria (mortality rate ratio 1.88, 95% CI 1.02-3.46, adjusted for age and sex). Mortality rate ratios for these risk factors were similar in subjects without RA. In addition, among subjects with RA, rheumatoid factor (RF) positivity was predictive of death (mortality rate ratio 1.94, 95% CI 1.10-3.43), and the excess mortality was found primarily among subjects who were seropositive. The death rate from cardiovascular disease (mortality rate ratio 1.77, 95% CI 1.10-2.84) and from liver cirrhosis or other alcohol-related disease (mortality rate ratio 2.52, 95% CI 1.06-6.01) was increased in persons with RA.
The results of this population-based study suggest that although the risk of mortality in subjects with RA is significantly higher than in those without RA, the risk ratio is in the lower range of that described previously in studies of clinic-based cohorts. RF positivity as a predictor of early death among subjects with RA indicates that the immunologic processes in seropositive RA may contribute to the events that eventually lead to early death.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Long since it have been suggested that a subpopulation of patients with rheumatoid arthritis (RA), diagnosed with negative rheumatoid factor (RF) tests, represents a clinical entity quite distinct from that of seropositive rheumatoid arthritis. The aim of the study was to establish a scientific comparative analysis between RA seronegative and seropositive, regarding course and prognoses of the disease. Two hundred fifty patients with rheumatoid arthritis according to the (American College of Rheumatology) criteria were retrospectively studied by analysis the course and prognoses of disease. All examinees were between 25-60 years of age (Xb=49.9, SD=10.3) with disease duration between 1-27 years (Xbox=6.41, SD=6.47). Course of the disease with "remissions and exacerbations", progressive continual course and bad prognoses, were more presented in seropositive group ofpatients. Partial remission was more common in seronegative patients but according to serostatus and gender has not shown statistically significant difference. Duration of the disease was a specific prognostic sign for both subsets [(r=0.32, p<0.01) seronegative, (r=0.22, p<0.05) seropositive], while age was only a specific prognostic sign for the seropositive subset [(r=0.01, p>0.05) seronegative, (r=0.18, p<0.05) seropositive]. Seropositive and seronegative RA distinguish in course and prognostic feature, but not enough to differentiate them in two different forms of the disease. Regarding the sero-status, differences within sex, with some exceptions, are not relevant.
    Reumatizam 01/2013; 60(1):19-24.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rheumatoid factors are antibodies directed against the Fc region of immunoglobulin G. First detected in patients with rheumatoid arthritis 70 years ago, they can also be found in patients with other autoimmune and nonautoimmune conditions, as well as in healthy subjects. Rheumatoid factors form part of the workup for the differential diagnosis of arthropathies. In clinical practice, it is recommended to measure anti-cyclic citrullinated peptide antibodies and rheumatoid factors together because anti-cyclic citrullinated peptide antibodies alone are only moderately sensitive, and the combination of the two markers improves diagnostic accuracy, especially in the case of early rheumatoid arthritis. Furthermore, different rheumatoid factor isotypes alone or in combination can be helpful when managing rheumatoid arthritis patients, from the time of diagnosis until deciding on the choice of therapeutic strategy.
    Disease markers 01/2013; 35(6):727-734. · 2.17 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Epidemiology is the study of the distribution and determinants of disease in human populations.21 This definition is based on two fundamental assumptions: first, that human disease does not occur at random and, second, that human disease has causal and preventive factors that can be identified through systematic investigation of different populations or subgroups of individuals within a population in different places or at different times. As a result, epidemiologic studies include simple descriptions of the manner in which disease appears in a population (i.e., levels of disease frequency as well as incidence and prevalence, mortality, trends over time, geographic distributions, and clinical characteristics) and descriptions of the role of putative risk factors for disease occurrence. Incidence studies include all new cases of a specified condition arising in a defined population over a specified time period, and prevalence studies include all patients with the condition who are present in a population at a particular point in time. As shown in Figure 1, prevalence cohorts exclude patients who died or left the population soon after their incidence date, and they include patients arising in different populations who moved into the cohort after their incidence date. Because of this, there is a greater potential for bias to be introduced in prevalence cohorts as compared to incidence cohorts. Thus, population-based incidence cohorts are superior to prevalence cohorts for descriptive epidemiologic studies. Epidemiologic studies of risk factors fall into three major categories: prospective cohort studies, retrospective cohort studies, and case-control studies. The relation between these is illustrated in Figure 2. In a prospective cohort study, a study population is assembled, none of whom have experienced the outcome of interest, and is followed forward into the future. People in the cohort are classified according to those characteristics that might be related to outcome, that is, putative risk factors. These people are then observed over time to determine which of them experience the outcome. The analysis addresses the question of whether people who were exposed to the risk factor were more likely to develop the outcome compared with those who were not exposed. In a retrospective cohort study, the cohort of individuals is identified from past records and followed forward up to the present. Data regarding historical exposure to the putative risk factor are collected retrospectively, typically by examination of medical records. As in a prospective cohort study, retrospective cohort studies also compare the frequency of the outcome in exposed patients as compared to unexposed patients. In a case-control study, two cohorts are assembled, one that has the outcome of interest and another that is free of the outcome of interest. Data regarding exposure to the putative risk factor in the two groups are collected retrospectively so as to determine whether patients with the outcome of interest were more likely to have had a history of the exposure of interest compared with those who were free of the outcome of interest. Of these three study designs, prospective cohort studies have fewer potential biases than the other two; however, they are frequently not feasible because they typically require extended follow-up, often 5 to 10 years or more into the future. A detailed comparison of the potential biases involved in retrospective cohort studies and case-control studies is beyond the scope of this article but can be readily found in numerous epidemiologic publications.21, 30 and 61 In this article, we review data on the descriptive epidemiology (incidence, prevalence, and survival) and risk factors associated with rheumatoid arthritis (RA).
    Rheumatic Disease Clinics of North America 05/2001; 27(2):269–281. · 1.74 Impact Factor