Long-Term Variability of Blood Pressure, Cardiovascular Outcomes, and Mortality: The Look AHEAD Study

Obesity prediction: Novel machine learning insights into waist circumference accuracy

AIMS

This study aims to enhance the precision of obesity risk assessments by improving the accuracy of waist circumference predictions using machine learning techniques.

METHODS

We utilized data from the NHANES and Look AHEAD studies, applying machine learning algorithms augmented with uncertainty quantification. Our approach centered on conformal prediction techniques, which provide a methodological basis for generating prediction intervals that reflect uncertainty levels. This method allows for constructing intervals expected to contain the true waist circumference values with a high degree of probability.

RESULTS

The application of conformal predictions yielded high coverage rates, achieving 0.955 for men and 0.954 for women in the NHANES dataset. These rates surpassed the expected performance benchmarks and demonstrated robustness when applied to the Look AHEAD dataset, maintaining coverage rates of 0.951 for men and 0.952 for women. Traditional point prediction models did not show such high consistency or reliability.

CONCLUSIONS

The findings support the integration of waist circumference into standard clinical practice for obesity-related risk assessments using machine learning approaches.

Long-term systolic blood pressure variability independent of mean blood pressure is associated with mortality and cardiovascular events: A systematic review and meta-analysis

The association between long-term systolic blood pressure variability (SBPV) and cardiovascular (CV) outcomes after being adjusted with mean blood pressure (BP) is questionable. This systematic review aims to evaluate the associations between mean BP adjusted long-term SBPV and CV outcomes. A systematic search was conducted on PubMed, Scopus, and Science Direct on January 4, 2023. A total of 9,944,254 subjects from 43 studies were included in this meta-analysis. Long-term SBPV increased the risk of all-cause mortality (HR 1.21 [95%CI 1.16-1.25], I2=100%), CV mortality (HR 1.10 [95%CI 1.07-11.4], I2 = 90%), MACE (HR 1.10 [1.07-1.13], I2 = 91%), cerebrovascular stroke (HR 1.22 [1.16-1.29], I2=100%), and myocardial infarction (HR 1.13 [95%CI (1.07-1.19)], I2=91%). European populations generally had higher risk compared to other continents. In conclusion, long-term SBPV is associated with all-cause mortality, CV mortality, MACE, MI, and stroke. Poor outcomes related to long-term SBPV seem more dominated by cerebrovascular than coronary events.

Exploration of cardiac rehabilitation nursing for elderly patients with myocardial infarction based on individualized cardiac rehabilitation

BACKGROUND

Myocardial infarction is a high-risk condition prevalent among the elderly population, often leading to adverse clinical manifestations such as reduced cardiopulmonary function, anxiety, and depression post-surgery. Consequently, cardiac rehabilitation holds immense importance in mitigating these complications.

AIM

To evaluate the effect of individualized cardiac rehabilitation on blood pressure variability (BPV) and baroreflex sensitivity (BRS) in elderly patients with myocardial infarction.

METHODS

A cohort of 74 elderly patients diagnosed with myocardial infarction and admitted to our hospital between January 2021 and January 2022 were subjected to random selection. Subsequently, all patients were divided into two groups, namely the research group (n = 37) and the control group (n = 37), utilizing the number table method. The control group received conventional drug treatment and nursing guidance intervention, while the study group underwent individualized cardiac rehabilitation in addition to the interventions received by the control group. All patients were continuously intervened for 12 wk, and the BPV of these two groups in the 1st wk (T0), the 4th wk (T1) and the 12th wk (T2) were compared, BRS, changes in cardiopulmonary function measures, and adverse cardiovascular events.

RESULTS

Of 24 h diastolic BPV, 24 h systolic BPV, carbon dioxide ventilation equivalent slope of the research group were lower than those of the control group at T1 and T2, BRS, peak heart rate and systolic blood pressure product, 1 min heart rate recovery were higher than those of the control group, and the incidence of adverse events in the research group was lower than that of the control group, the difference was statistically significant (P < 0.05).

CONCLUSION

In this study, we found that after individualized cardiac rehabilitation in elderly patients with myocardial infarction, BPV and BRS can be effectively improved, cardiac function is significantly enhanced, and a better prognosis is obtained.

Blood Pressure Variability and Risk of Atrial Fibrillation in Adults With Type 2 Diabetes

BACKGROUND

There is a paucity of epidemiological data on the association between long-term variability of blood pressure (BP) and incident atrial fibrillation (AF).

OBJECTIVES

The purpose of this study was to evaluate the association of BP variability with incident AF in a large sample of adults with type 2 diabetes.

METHODS

We included participants who had ≥5 BP measurements in the first 24 months of action to control cardiovascular risk in diabetes. The visit-to-visit variability of systolic blood pressure (SBP) and diastolic blood pressure (DBP) was estimated using the coefficient of variation, SD, and variability independent of the mean. Incident AF was recorded using follow-up electrocardiograms. Modified Poisson regression was used to generate risk ratios (RRs) and 95% CI for AF.

RESULTS

A total of 8,399 participants were included (average age 62.6 ± 6.5 years, 38.8% women, 63.2% White). Over a median follow-up of 5 years, 155 developed AF. Compared to the lowest quartile, the highest quartile of BP variability was associated with an increased risk of AF (RR: 1.85 [95% CI: 1.13-3.03] and 1.63 [95% CI: 1.01-2.65] for coefficient of variation of SBP and DBP, respectively). Participants in the highest quartile of both SBP and DBP had a 2-fold higher risk of AF compared to those in the lowest 3 quartiles of both SBP and DBP (RR: 1.94; 95% CI: 1.29-2.93).

CONCLUSIONS

In a large cohort of adults with type 2 diabetes, higher variability in SBP and DBP was independently associated with an increased risk of AF.

Visit-to-visit variability in blood pressure and kidney disease progression in IgA nephropathy

Background

The visit-to-visit variability (VVV) in blood pressure (BP) is an important risk factor for stroke and coronary heart disease and may also be associated with kidney damage and the development of chronic kidney disease (CKD). Data on the association between VVV in BP and the risk of CKD progression among patients with immunoglobulin A nephropathy (IgAN) are limited. We aimed to evaluate the relationships of VVV in BP with the progression of IgAN.

Methods

We assessed 1376 patients with IgAN at Peking University First Hospital. The main VVV in BP was expressed as the standard deviation (SD), coefficient of variation (CV) and average real variability (ARV). The associations of variability in BP with composite kidney disease progression events, defined as a 50% decline in estimated glomerular filtration rate (eGFR) and kidney failure, were examined using Cox models.

Results

During a median follow-up of 44.1 months (interquartile range 23.0–76.7), 247 (18.0%) patients experienced composite kidney disease progression events. With a higher SD in systolic BP (SBP) values, the risk of kidney disease progression events increased {hazard ratio [HR] 1.07 [95% confidence interval (CI) 1.03–1.11]; P < .001} after maximal adjustment, including baseline SBP and mean SBP during the first 12-month period. Using the first quartile of SD SBP values as the reference, the risk of composite kidney disease progression events was higher among patients with higher SD SBP values; the HR was 2.12 (95% CI 1.31–3.44) in the highest quartile (P for trend < .001). A similar trend could be observed when analysing the SD of diastolic BP, but the risk was not significantly increased. The associations were similar when analysed with the CV and ARV.

Conclusion

SBP variability was significantly associated with kidney disease progression in IgAN.