APOE and Alzheimer disease: Therefore, we performed a multicenter study to estimate the proportion of the primary hypometabolic pattern in a large sample of patients with a variety of MCI and dementia syndromes, evaluate the associations between AD‐pattern (AD‐P) and frontotemporal lobe‐pattern (FT‐P) hypometabolism and NPS, and examine the apolipoprotein E (APOE) ε4 allele, amyloid‐β (Aβ), or Tau deposition on PET scans in this cohort of patients.