Identification of dementia and MCI cases in health information systems: An Italian validation study.

Introduction: The identification of dementia cases through routinely collected health data represents an easily accessible and inexpensive method to estimate the prevalence of dementia. In Italy, a project aimed at the validation of an algorithm was conducted. Methods: The project included cases (patients with dementia or mild cognitive impairment [MCI]) recruited in centers for cognitive disorders and dementias and controls recruited in outpatient units of geriatrics and neurology. The algorithm based on pharmaceutical prescriptions, hospital discharge records, residential long-term care records, and information on exemption from health-care co-payment, was applied to the validation population. Results: The main analysis was conducted on 1110 cases and 1114 controls. The sensitivity, specificity, and positive and negative predictive values in discerning cases of dementia were 74.5%, 96.0%, 94.9%, and 79.1%, respectively, whereas in detecting cases of MCI these values were 29.7%, 97.5%, 92.2%, and 58.1%, respectively. The variables associated with misclassification of cases were also identified. Discussion: This study provided a validated algorithm, based on administrative data, which can be used to identify cases with dementia and, with lower sensitivity, also early onset dementia but not cases with MCI.

Effects of low blood pressure in cognitively impaired elderly patients treated with antihypertensive drugs.

IMPORTANCE: The prognostic role of high blood pressure and the aggressiveness of blood pressure lowering in dementia are not well characterized. OBJECTIVE: To assess whether office blood pressure, ambulatory blood pressure monitoring, or the use of antihypertensive drugs (AHDs) predict the progression of cognitive decline in patients with overt dementia and mild cognitive impairment (MCI). DESIGN, SETTING, AND PARTICIPANTS: Cohort study between June 1, 2009, and December 31, 2012, with a median 9-month follow-up of patients with dementia and MCI in 2 outpatient memory clinics. MAIN OUTCOMES AND MEASURES: Cognitive decline, defined as a Mini-Mental State Examination (MMSE) score change between baseline and follow-up. RESULTS: We analyzed 172 patients, with a mean (SD) age of 79 (5) years and a mean (SD) MMSE score of 22.1 (4.4). Among them, 68.0% had dementia, 32.0% had MCI, and 69.8% were being treated with AHDs. Patients in the lowest tertile of daytime systolic blood pressure (SBP) (≤ 128 mm Hg) showed a greater MMSE score change (mean [SD], -2.8 [3.8]) compared with patients in the intermediate tertile (129-144 mm Hg) (mean [SD], -0.7 [2.5]; P = .002) and patients in the highest tertile (≥ 145 mm Hg) (mean [SD], -0.7 [3.7]; P = .003). The association was significant in the dementia and MCI subgroups only among patients treated with AHDs. In a multivariable model that included age, baseline MMSE score, and vascular comorbidity score, the interaction term between low daytime SBP tertile and AHD treatment was independently associated with a greater cognitive decline in both subgroups. The association between office SBP and MMSE score change was weaker. Other ambulatory blood pressure monitoring variables were not associated with MMSE score change. CONCLUSIONS AND RELEVANCE: Low daytime SBP was independently associated with a greater progression of cognitive decline in older patients with dementia and MCI among those treated with AHDs. Excessive SBP lowering may be harmful for older patients with cognitive impairment. Ambulatory blood pressure monitoring can be useful to help avoid high blood pressure overtreatment in this population.

Tolerability of ambulatory blood pressure monitoring (ABPM) in cognitively impaired elderly.

OBJECTIVE: Recent guidelines have widened clinical indications for out-of-office blood pressure measurement, including home blood pressure monitoring and ambulatory blood pressure monitoring (ABPM), suggesting the latter as recommended method in cognitively impaired patients. There is, however, a widespread belief that ABPM could be poorly tolerated in dementia, often leading to withdraw from its use in these patients. AIM: To assess the actual tolerability of ABPM in a group of cognitively impaired elderly, affected by dementia or mild cognitive impairment (MCI). METHODS: We evaluated 176 patients aged 65 + years, recruited in two different memory clinics, with a Mini Mental State Examination (MMSE) between 10 and 27. Behavioral and psychological symptoms were assessed with Neuropsychiatric Inventory (NPI). A patient was considered tolerant if able to keep the device on continuously for 24 h. The minimum number of correct measurements required was 70% of the predicted total number. RESULTS: 16% of patients wore the device for less than 24 h. Dividing the study population in tertiles of MMSE performance, 29% failed to tolerate the device in the lowest, 12% in the middle and 7% in the highest tertile (p < 0.01). Dividing the study population in tertiles of NPI performance, 30% of patients failed in the highest, 19% in the middle and 8% in the lowest tertile (p = 0.02); 31% of patients who tolerated the device did not achieve the minimum number of measurements required, with a mean number of 63% of predicted measurements. CONCLUSION: The ABPM proved a generally well-tolerated technique even in cognitively impaired elderly. Only a minority of subjects with poorer cognitive performances and greater behavioral symptoms did not tolerate the monitoring. Among most patients who failed to achieve the minimum number of measurements needed, the number of valid measurements was very close to the minimum required.