Higher BMI Confers a Long-Term Functional Status Advantage in Elderly New Zealand European Stroke Patients

J Stroke Cerebrovasc Dis. 2021 May;30(5):105711. doi: 10.1016/j.jstrokecerebrovasdis.2021.105711. Epub 2021 Mar 10.

Abstract

Objective: Obesity is a risk factor for ischaemic stroke but provides a survival advantage. The relationship between body mass index (BMI) and long-term function is less clear. The presence of an obesity paradox can inform clinical care and identify vulnerable patients who need additional support post-stroke.

Materials and methods: This study used linked health administrative data of a population based cohort of adult patients who experienced an ischaemic stroke between 2012 and 2017 in New Zealand. Patient demographics were obtained from the National Minimum Dataset (NMDS). BMI and Activities of Daily Living scores (ADLs) for the same patients were obtained from the International Resident Assessment Instrument (InterRAI™).

Results: Linked data was obtained for 3731 patients. Ninety-five percent of the cohort were aged 65 or older and the average age of stroke was 84.5 years. The majority of patients (55%) identified as New Zealand European. Beta regression indicated BMI and European ethnicity were negatively associated with ADL score. Univariate analysis confirmed patients with underweight stroke had significantly higher ADL scores than other BMI categories (p<0.001), however functional status for patients with overweight and obesity were comparable. Further, Asian and Pacific Peoples had higher ADL scores than Europeans (p<0.05). A higher BMI was advantageous to all ADL subscores.

Conclusion: An abridged obesity paradox was evident in our cohort of stroke patients where a BMI in the overweight, but not obese range conferred a long-term functional status advantage. Collectively these results suggest underweight and non-European patients may require additional supportive clinical care post-stroke.

Keywords: ADL score; BMI; Functional status; Ischemic stroke; Obesity paradox.

Publication types

  • Comparative Study
  • Observational Study

MeSH terms

  • Age Factors
  • Aged
  • Aged, 80 and over
  • Body Mass Index*
  • Female
  • Functional Status*
  • Geriatric Assessment
  • Humans
  • Ischemic Stroke / diagnosis
  • Ischemic Stroke / mortality
  • Ischemic Stroke / physiopathology
  • Ischemic Stroke / therapy*
  • Male
  • Middle Aged
  • New Zealand
  • Overweight / diagnosis*
  • Overweight / mortality
  • Overweight / physiopathology
  • Prognosis
  • Protective Factors
  • Retrospective Studies
  • Risk Assessment
  • Risk Factors
  • Thinness / diagnosis*
  • Thinness / mortality
  • Thinness / physiopathology