A simple score to screen for isolated ambulatory hypertension in older adults. Development and validation

Introduction and objectives Masked or isolated ambulatory hypertension (IAH), a poor-prognosis condition, can be diagnosed with ambulatory blood pressure monitoring (ABPM), but ABPM is not available in many clinical practices. We developed and validated a score to screen for IAH among older adults, where limited information is available. Methods A total of 645 community-dwelling adults≥65 years from the Seniors-ENRICA-2 cohort (derivation sample) and 327 from the Seniors-ENRICA-1 cohort (external-validation sample), with untreated casual BP<140/90mmHg (mean of the last 2 of 3 BP) were examined. Probabilities of having IAH (mean 24-h ambulatory BP≥130/80mmHg) were calculated with a multivariable model (with sex, age, and clinical variables). Beta coefficients were used to allocate points to each variable in an IAH score (range, 0–12). Results Participants’ mean age was 70.8 years (46.7% men); 19.7% had IAH. Allocated score-points were: male sex (1 point), age≥80 (2 points), body-mass index (2 points if 25–29; 3 if ≥30kg/m2), the first BP measurement (2 points if ≥140/90mmHg), and the mean of the second and third BP (2 points if 120–129/80–84; 4 if 130–139/85–89). Probabilities of having IAH for scores of 6, 7, 8, 9, or ≥10 points were 25%, 35%, 47%, 59%, and 72%, respectively. Area-under-the-ROC curve was 0.80 for the derivation and 0.73 for the validation-sample. Two subjects at high risk of IAH (>8 points) and 3 at middle risk (≥6) needed to undergo ABPM to detect 1 IAH case. Conclusions A simple score with 4 routine variables performed well identifying IAH in older adults. For high scores, using ABPM for diagnosing IAH was very size-efficient.