Non-HDL cholesterol paradox and effect of underlying malnutrition in patients with coronary artery disease: a 41,182 cohort study

Serum Cholesterol and Impact of Age on Coronary Heart Disease Death in More Than 4 Million Veterans

Background The lipid hypothesis postulates that lower blood cholesterol is associated with reduced coronary heart disease (CHD) risk, which has been challenged by reports of a U-shaped relation between cholesterol and death in recent studies. We sought to examine whether the U-shaped relationship is true and to assess the impact of age on this association. Method and Results We conducted a prospective cohort study of 4 467 942 veterans aged >18 years, with baseline outpatient visits from 2002 to 2007 and follow-up to December 30, 2018, in the Veterans Health Administration electronic health record system. We observed a J-shaped relation between total cholesterol (TC) and CHD mortality after a comprehensive adjustment of confounding factors: flat for TC <180 mg/dL, and greater risk was present at higher cholesterol levels. Compared with veterans with TC between 180 and 199 mg/dL, the multiadjusted hazard ratios (HRs) for CHD death were 1.03 (95% CI, 1.02-1.04), 1.07 (95% CI, 1.06-1.09), 1.15 (95% CI, 1.13-1.18), 1.25 (95% CI, 1.22-1.28), and 1.45 (95% CI, 1.42-1.49) times greater among veterans with TC (mg/dL) of 200 to 219, 220 to 239, 140 to 259, 260 to 279 and ≥280, respectively. Similar J-shaped TC-CHD mortality patterns were observed among veterans with and without statin use at or before baseline. Conclusions The cholesterol paradox, for example, higher CHD death in patients with a low cholesterol level, was a reflection of reverse causality, especially among older participants. Our results support the lipid hypothesis that lower blood cholesterol is associated with reduced CHD. Furthermore, the hypothesis remained true when TC was low due to use of statins or other lipid-lowering medication.

The Paradoxical Association of Lipids with Survival and Walking Ability of Hip Fractures in Geriatric Patients After Surgery: A 1-Year Follow-Up Study

Background

We aimed to explore the association between lipids and the survival and walking ability of hip fractures in geriatric patients after surgery.

Methods

Restricted cubic spline (RCS) was established to explore the nonlinear relationship between lipids and 1-year mortality of hip fractures, and the cut-off points were also determined by RCS. Then, the patients were divided into three groups: low, middle, and high levels of LDL-c. Then, the survival and walking ability of patients from different groups were compared, and the Cox regression and Logistics regression were used to identify the relationships between lipids and the survival and walking ability of hip fractures.

Results

The patients with middle levels of LDL-c had a significantly high survival probability than those with low or high levels of LDL-c (p < 0.001). The patients with low levels of LDL-c and with high levels of LDL-c may have a poor prognosis compared with patients with middle levels of LDL-c in 6-month mortality, 6-month free walking ability, 1-year mortality, and 1-year free walking ability (All p < 0.05).

Conclusion

Low and high levels of LDL-c may both relate to the poor survival and walking ability of hip fractures.

U-Shaped Relationship of Non-HDL Cholesterol With All-Cause and Cardiovascular Mortality in Men Without Statin Therapy

Background

Non-HDL-C is well established causal risk factor for the progression of atherosclerotic cardiovascular disease. However, there remains a controversial pattern of how non-HDL-C relates to all-cause and cardiovascular mortality, and the concentration of non-HDL-C where the risk of mortality is lowest is not defined.

Methods

A population-based cohort study using data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2014. Male participants without statin therapy were divided into the six groups according to non-HDL-C levels (<100, 100–129, 130–159, 160–189, 190–219, ≥220 mg/dl). Multivariable Cox proportional hazards models were conducted with a hazard ratio (HR) and corresponding 95% confidence interval (CI). To further explore the relationship between non-HDL-C and mortality, Kaplan–Meier survival curves, restricted cubic spline curves, and subgroup analysis were performed.

Results

Among 12,574 individuals (average age 44.29 ± 16.37 years), 1,174(9.34%) deaths during a median follow-up 98.38 months. Both low and high non-HDL-C levels were significantly associated with increased risk of all-cause and cardiovascular mortality, indicating a U-shaped association. Threshold values were detected at 144 mg/dl for all-cause mortality and 142 mg/dl for cardiovascular mortality. Below the threshold, per 30 mg/dl increase in non-HDL-C reduced a 28 and 40% increased risk of all-cause (p < 0.0001) and cardiovascular mortality (p = 0.0037), respectively. Inversely, above the threshold, per 30 mg/dl increase in non-HDL-C accelerated risk of both all-cause mortality (HR 1.11, 95% CI 1.03–1.20, p = 0.0057) and cardiovascular mortality (HR 1.30, 95% CI 1.09–1.54, p = 0.0028).

Conclusions

Non-HDL-C was U-shaped related to all-cause and cardiovascular mortality among men without statin therapy.