Disability in XXXX -- a longitudinal observational study.

@entity1 @entity66 @entity2631 @entity785
OBJECTIVE: To assess disability in @entity785 ( @entity785 ) longitudinally and to identify disease-specific determinants, after accounting for informative @entity1 dropout. METHODS: We performed a multicenter, longitudinal study of 745 @entity1 with @entity785 followed in the Canadian @entity2631 Research Group registry. Disability was assessed using the Health Assessment Questionnaire (HAQ). Longitudinal changes in disability were modeled using statistical approaches accounting for various levels of @entity1 dropout. RESULTS: In all the models, disability in @entity785 worsened over time. The magnitude of the worsening was small when @entity1 dropout was assumed to be completely at random (increase in the HAQ of 0.022, 95% CI 0.002-0.042, per year). After accounting for different levels of informative @entity1 dropout, the increase in the HAQ ranged from 0.039 (95% CI 0.018-0.061) per year to 0.071 (95% CI 0.048-0.094) per year. Thus, using the most conservative of these estimates, this was equivalent to an increase in the HAQ of 0.12 over 3 years. The disease correlates found to be most closely associated with disability were @entity66 and breathing problems. CONCLUSION: Our study provides strong evidence that @entity785 causes increased disability over time, with breathing problems and disease type being the strongest predictors of disability. Statistical modeling accounting for informative @entity1 dropout is necessary to properly assess the outcomes of @entity1 followed longitudinally.
