Some empirical studies have identified the prevalence of, and factors associated with, obesity among the oldest old. However, there is a lack of a systematic review synthesizing the existing evidence. Therefore, the purpose of our upcoming systematic review is to provide an overview of the evidence provided by observational studies. The current paper presents the protocol for this systematic review. We will search four electronic databases (Medline, PsycINFO, CINAHL, and Cochrane Library). Furthermore, we will perform a manual search (searching reference lists of included studies). Cross-sectional and longitudinal observational studies identifying the prevalence and preferably the factors associated with obesity among the oldest old (80 years and over) will be included. Data extraction will concentrate on study design, assessment of obesity and its associated factors, statistical analysis, sample characteristics, and key findings. We will evaluate the quality of the included studies. Two individuals will perform study selection, data extraction, and evaluation of study quality. We will present the results in figures, summary tables and narrative summaries. If data permits, a meta-analysis will be conducted.
Keywords: 80 and over; adiposity; aged; body-mass-index; excess weight; obesity; oldest old; overweight; systematic review; underweight.