Based on findings from a systematic literature review, patients with AD are more likely to have cardiovascular disease, including stroke than individuals without AD.1 In most studies, diabetes was slightly more common in patients with AD compared with controls, or prevalence was similar between groups.1 However, no clear pattern was apparent for hypertension as prevalence ranged from 41.5% to 72.1% in patients with AD and 40.4% to 73.2% in controls.1 Additionally, it was found that individuals with AD have increased mortality compared with individuals without AD.1 The systematic literature review aimed to characterize AD and estimate its burden on affected individuals.1 While the review aimed to focus on studies reporting data for AD dementia of mild cognitive impairment (MCI) due to AD, several studies grouped AD with either all-cause MCI, or other types of dementia.1 Disparities across studies regarding age, setting, ascertainment method, and staging of AD dementia were also found.1 It is likely that some people considered to have AD dementia in the studies included in the systematic literature review may have been misdiagnosed, or had other concomitant diagnoses, which should be taken into account when interpreting the results.1
Comorbidities such as depression and type 2 diabetes are associated with an increased risk of progression from MCI to AD.2 Identifying and correctly addressing comorbid conditions is therefore important for providing personalized treatment.3 Due to shared genetics, environmental factors, and strong competing risk of death with different conditions, the mechanisms underlying the association between comorbid diseases and AD remain poorly understood.3 While some genetic factors contribute to the development of late-onset AD, genetics alone does not account for the majority of cases.3 Several comorbidities that are associated with AD are linked to dysregulated metabolic pathways, suggesting that lifestyle factors are important factors in disease pathogenesis.3