Aims

Hypokalaemia is a risk factor for ventricular arrhythmias and sudden death in ambulatory patients with chronic heart failure (HF). The objective of this study was to examine the association between hypokalaemia and outcomes in hospitalized patients with decompensated HF in whom sudden death is less common.

Methods and results

Of the 5881 hospitalized patients with HF, 1052 had consistent hypokalaemia (both admission and discharge serum potassium <4.0 mmol/L), and 2538 had consistent normokalaemia (both admission and discharge serum potassium 4.0-5.0 mmol/L). Propensity scores for consistent hypokalaemia, estimated for each of 3590 (1052 + 2538) patients, were used to assemble a matched cohort of 971 pairs of patients with consistent hypokalaemia vs. consistent normokalaemia, balanced on 54 baseline characteristics (mean age, 75 years; 60% women; 28% African American). We repeated the above process to assemble 2327 pairs of patients with discharge potassium <4.0 vs. 4.0-5.0 mmol/L and 449 pairs of patients with discharge serum potassium <3.5 vs. 4.0-5.0 mmol/L. Hazard ratios (HR) and 95% confidence intervals (CIs) associated with hypokalaemia were estimated in matched cohorts. 30 day all-cause mortality occurred in 5% and 4% of patients with consistent normokalaemia vs. consistent hypokalaemia, respectively (HR, 0.78; 95% CI, 0.52-1.18; P = 0.241). HRs (95% CI) for 30 day mortality associated with discharge serum potassium <4.0 and <3.5 mmol/L were 0.90 (0.70-1.16; P = 0.419) and 1.69 (0.94-3.04; P = 0.078), respectively. Hypokalaemia (<4.0 or <3.5 mmol/L) had no association with long-term mortality or other outcomes.

Conclusions

In hospitalized older patients with HF, compared with normokalaemia (serum potassium 4.0-5.0 mmol/L), hypokalaemia (<4.0 or <3.5 mmol/L) had no significant associations with outcomes.

Background

Isolated systolic hypertension and isolated diastolic hypotension are common in older adults and associated with a higher risk of incident heart failure (HF). However, little is known about the prevalence and impact of isolated diastolic hypertension in this population.

Methods

In the Cardiovascular Health Study (CHS), of the 5776 community-dwelling older adults ≥65years who had data on baseline systolic and diastolic blood pressure (SBP and DBP), 28 had isolated diastolic hypertension (DBP ≥90mmHg and SBP <140mmHg). From the 5748 without isolated diastolic hypertension, we excluded those with SBP ≥120mmHg (n=4451), DBP 80-89mmHg (n=20), DBP <60mmHg (n=425), normal BP taking anti-hypertensive medications (n=311), normal BP taking no anti-hypertensive medications but with history of hypertension (n=38), and baseline HF (n=5). The final cohort of 524 participants included 27 with isolated diastolic hypertension.

Results

Patients (n=524) had a mean (±SD) age of 71 (±5) years, 58% were women and 9% African American. There were no significant between-group age or sex differences; 37% of those with isolated diastolic hypertension (versus 7% without) were African American. Incident HF occurred in 19% and 7% of participants with and without isolated diastolic hypertension, respectively (multivariable-adjusted hazard ratio {HR}, 4.65; 95% confidence interval {CI}, 1.09-19.90; p=0.038). There was a trend toward higher cardiovascular mortality (HR, 4.59; 95% CI, 0.92-23.88; p=0.063).

Conclusion

Among community-dwelling older adults, isolated diastolic hypertension is rare and is associated with higher risk for incident HF and cardiovascular mortality.

Background

Isolated systolic hypertension (ISH) is common in older adults and is a risk factor for incident heart failure (HF). We examined the association of systolic-diastolic hypertension (SDH) with incident HF and other outcomes in older adults.

Methods

In the Cardiovascular Health Study (CHS), 5776 community-dwelling adults≥65years had data on baseline systolic and diastolic blood pressure (SBP and DBP). We excluded those with DBP<60mmHg (n=821), DBP≥90 and SBP<140mmHg (n=28), normal BP, taking anti-hypertensive drugs (n=1138), normal BP, not taking anti-hypertensive drugs, history of hypertension (n=193), and baseline HF (n=101). Of the remaining 3495, 1838 had ISH (SBP≥140 and DBP<90mmHg) and 240 had SDH (SBP≥140 and DBP≥90mmHg). The main outcome was centrally-adjudicated incident HF over 13years of follow-up.

Results

Participants had a mean (±SD) age of 73 (±6)years, 57% were women, and 16% African American. Incident HF occurred in 25%, 22% and 11% of participants with ISH, SDH and no hypertension, respectively. Compared to no hypertension, multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for incident HF associated with ISH and SDH were 1.86 (1.51-2.30) and 1.73 (1.23-2.42), respectively. Cardiovascular mortality occurred in 22%, 24% and 9% of those with ISH, SDH and no hypertension, respectively with respective multivariable-adjusted HRs (95% CIs) of 1.88 (1.49-2.37) and 2.30 (1.64-3.24).

Conclusion

Among older adults with hypertension, both SDH and ISH have similar associations with incident HF and cardiovascular mortality.