Assessing nonresponse bias at follow-up in a large prospective cohort of relatively young and mobile military service members

<p>Abstract</p> <p>Background</p> <p>Nonresponse bias in a longitudinal study could affect the magnitude and direction of measures of association. We identified sociodemographic, behavioral, military, and health-related predictors of response to the first follow-up questionnaire in a large military cohort and assessed the extent to which nonresponse biased measures of association.</p> <p>Methods</p> <p>Data are from the baseline and first follow-up survey of the Millennium Cohort Study. Seventy-six thousand, seven hundred and seventy-five eligible individuals completed the baseline survey and were presumed alive at the time of follow-up; of these, 54,960 (71.6%) completed the first follow-up survey. Logistic regression models were used to calculate inverse probability weights using propensity scores.</p> <p>Results</p> <p>Characteristics associated with a greater probability of response included female gender, older age, higher education level, officer rank, active-duty status, and a self-reported history of military exposures. Ever smokers, those with a history of chronic alcohol consumption or a major depressive disorder, and those separated from the military at follow-up had a lower probability of response. Nonresponse to the follow-up questionnaire did not result in appreciable bias; bias was greatest in subgroups with small numbers.</p> <p>Conclusions</p> <p>These findings suggest that prospective analyses from this cohort are not substantially biased by non-response at the first follow-up assessment.</p

The life-course impact of smoking on hypertension, myocardial infarction and respiratory diseases

The Author(s) 2017. The objective of this study was to examine the impact of smoking on respiratory diseases, hypertension and myocardial infarction, with a particular focus from a life-course perspective. In this study, 28,577 males from a Chinese longitudinal survey were analysed. The effects of smoking on the risk of respiratory diseases, hypertension and myocardial infarction were assessed from a life-course perspective and a current view separately. No significant associations were found between smoking and the risk of incident respiratory diseases, hypertension and myocardial infarction in the group younger than 35. Among study participants aged between 36-55 and 56-80, smoking was positively associated with the risk of incident respiratory diseases, hypertension and myocardial infarction from the life-course perspective, and the risk increased with age. In contrast, the results from a current view showed inverse associations between smoking and the risk of the diseases mentioned above. Our findings highlight that it is essential to quantify the effects of smoking from a life-course perspective in future research and to suggest that smokers quit smoking as soon as possible, regardless of the temporary side effects of quitting

Concurrent musculoskeletal and soft tissue pain in the upper extremity can affect the treatment and prognosis of carpal tunnel syndrome: redefining a common condition

Reynaldo P Lazaro,1 Thomas S Eagan2 1Electroneuromyography Clinic, Oneonta, NY, USA; 2Department of Orthopedic Surgery, Orthopedic and Hand Surgery and Wellness Center, Nathan Littauer Hospital, Gloversville, NY, USA Objective: To demonstrate the importance of recognizing and separating nonmedian nerve-related symptoms from those related to median nerve compression at the carpal tunnel. Methods: The records of 80 patients, aged 31&ndash;82 years (39 males and 41 females), who had undergone median nerve decompression using open and endoscopic release surgery, were reviewed. Peripheral electrodiagnostic studies were performed in all patients prior to surgery. Those whose nonmedian nerve-related symptoms, also known as musculoskeletal and soft tissue pain and tenderness, persisted postoperatively, were referred to another electrodiagnostic study to reassess the median nerve function at the carpal tunnel. Peripheral electrodiagnostic studies were deemed unnecessary for patients with exclusively median nerve-related symptoms who improved dramatically following surgery. Included from the study were cases whose presenting symptoms were primarily referrable to median nerve dysfunction with or without associated musculoskeletal pain. Cases that were excluded were those whose symptoms were related to various primary conditions. Outcome of surgery was reviewed and correlated with symptoms related to median nerve compression and musculoskeletal irritation, and with electrodiagnostic abnormalities. Results: Complete resolution of symptoms, following surgery, occurred in patients with clinical and electrophysiologic signs of median nerve compression but without significant symptoms of musculoskeletal irritation. Those with concurrent and prominent musculoskeletal and soft tissue pain had variable results, both favorable and unfavorable, including three who developed signs and symptoms of complex regional pain syndrome. Conclusion: The symptoms related to median nerve compression at the carpal tunnel and the symptoms related to musculoskeletal and soft tissue irritation are two different symptom complexes that have important diagnostic and therapeutic considerations. We would like to propose that &ldquo;true carpal tunnel syndrome&rdquo; symptoms, those that are exclusively median nerve related, should be considered a distinct entity. When musculoskeletal and soft tissue pain is more prominent and dominates the overall clinical presentation, the term &ldquo;mechanical stress syndrome&rdquo; is more appropriate. Keywords: median nerve, carpal tunnel syndrome, musculoskeletal pain, soft tissue pain, complex regional pain, mechanical stress syndrome, repetitive hand motio

Current Serum Lipoprotein Levels and fMRI Response to Working Memory in Midlife

Aims: Given that high cholesterol levels at midlife are a risk factor for future cognitive decline, the goal of the current study was to determine if cholesterol-related alterations in the cerebrovascular response to cognition could be detected at midlife. Methods: Forty adults, aged 40-60 years, performed a 2-Back working memory task during fMRI. The associations between serum total cholesterol, HDL-cholesterol, and total cholesterol/HDL-cholesterol concentrations to task-related activation intensity were modeled using multivariate multiple regression (two-tailed p \u3c 0.02). Results: Higher levels of total cholesterol/HDL-cholesterol related to reduced working memory-related activation intensity in the left inferior parietal lobe, right superior frontal gyrus, and right middle frontal gyrus. Conclusion: These data provide preliminary support for a deleterious effect of elevated total cholesterol/HDL-cholesterol ratio on cerebrovascular support for cognition in midlife. Copyright © 2011 S. Karger AG, Basel