Association of remnant cholesterol with risk of dementia: a nationwide population-based cohort study in South Korea.

BACKGROUND: The association between remnant cholesterol (remnant-C) and cardiovascular disease risk is well established, but its association with dementia remains unclear. We aimed to examine this association using a large-scale population dataset. METHODS: We did a nationwide, population-based cohort study in which we identified participants aged 40 years and older who underwent the national health examination in 2009 from South Korea's National Health Insurance Service. We excluded people who were younger than 40 years and those with a triglyceride concentration of 400 mg/dL or higher due to concerns regarding the accuracy of calculated low-density lipoprotein cholesterol concentration in individuals with extremely high triglyceride concentrations. People who were previously diagnosed with dementia before the index date, and those who had any missing variables were also excluded. To minimise the influence of possible reverse causation, we excluded individuals who had developed any type of dementia within 1 year of the baseline measurements. We calculated hazard ratios (HRs) for all-cause dementia, Alzheimer's disease, and vascular dementia in each quartile of remnant-C using the Cox proportional hazards model adjusted for age, sex, body-mass index, estimated glomerular filtration rate, income level, smoking status, alcohol consumption, regular exercise, diabetes, hypertension, statin and fibrate use, and total cholesterol concentrations. We also did subgroup analyses to investigate the association between remnant-C and the risk of dementia stratified by age, sex, obesity, glycaemic status (normoglycaemia, impaired fasting glucose, new-onset type 2 diabetes, type 2 diabetes with a duration of less than 5 years, and type 2 diabetes with a duration of 5 years or more), hypertension, chronic kidney disease, and dyslipidaemia, using likelihood ratio tests. FINDINGS: 4 234 415 individuals who underwent the national health examination in 2009 were deemed eligible for inclusion. We excluded 1 612 819 individuals on the basis of age, triglyceride concentration, missing variables, or having dementia at baseline. We identified 2 621 596 participants aged 40 years and older (1 305 556 men and 1 316 040 women) who underwent the national health examination and followed them up until the date of any incident of dementia or the end of the study period of Dec 31, 2020. During a median follow-up of 10·3 years (IQR 10·1-10·6), 146 991 (5·6%) participants developed all-cause dementia, 117 739 (4·5%) developed Alzheimer's disease, and 14 536 (0·6%) developed vascular dementia. The risk of dementia increased progressively with higher remnant-C concentrations. Compared with the lowest quartile of remnant-C (quartile 1), HRs in the highest quartile (quartile 4) were 1·11 (95% CI 1·09-1·13) for all-cause dementia, 1·11 (1·08-1·13) for Alzheimer's disease, and 1·15 (1·09-1·21) for vascular dementia. Subgroup analyses revealed that the risk of dementia associated with high remnant-C concentrations was higher in middle-aged people aged 40-59 years than in older people. The risk of dementia associated with high concentrations of remnant-C was notably more pronounced in individuals with diabetes compared with those without diabetes, and the risk increased steeply with a longer duration of diabetes. INTERPRETATION: Results showed that higher remnant-C concentrations were independently associated with increased risks of all-cause dementia, Alzheimer's disease, and vascular dementia. More research is needed to determine the mechanisms underlying this finding. Monitoring and managing higher concentrations of remnant-C might have important implications for reducing the risk of dementia. FUNDING: None.

Dual add-on therapy of gemigliptin and dapagliflozin in patients with type 2 diabetes inadequately controlled with metformin alone: The SOLUTION 2 study.

AIM: To evaluate the efficacy and safety of gemigliptin and dapagliflozin dual add-on therapy (GEMI + DAPA) to metformin in type 2 diabetes (T2D) patients who had inadequate glycaemic control on metformin alone, compared with a single add-on of either gemigliptin (GEMI) or dapagliflozin (DAPA) to metformin. MATERIALS AND METHODS: In this randomized, double-blind, double-dummy, active-controlled, parallel-group, phase 3 study, 469 T2D patients treated with a stable dose of metformin for 8 weeks or longer were randomized to receive GEMI + DAPA (n = 157) and either GEMI (n = 156) or DAPA (n = 156). The primary endpoint was change in HbA1c levels from baseline at week 24. RESULTS: Baseline characteristics including body mass index and T2D duration were similar among groups. At week 24, the least square mean changes in HbA1c from baseline were -1.34% with GEMI + DAPA, -0.90% with GEMI (difference between GEMI + DAPA vs. GEMI -0.44% [95% confidence interval {CI}: -0.58% to -0.31%], P < .01) and -0.78% with DAPA (difference between GEMI + DAPA vs. DAPA -0.56% [95% CI: -0.69% to -0.42%], P < .01). Both upper CIs were less than 0, demonstrating the superiority of GEMI + DAPA for lowering HbA1c. The rates of responders achieving HbA1c less than 7% and less than 6.5% were greater with GEMI + DAPA (84.9%, 56.6%) than with GEMI (55.3%, 32.2%) and DAPA (49.3%, 15.3%). The incidence rate of adverse events was similar across groups, with low incidence rates of hypoglycaemia, urinary tract infection and genital infection. CONCLUSIONS: These results suggest that the addition of GEMI + DAPA to metformin as triple combination therapy was effective, safe and well-tolerated, especially for T2D patients who experienced poor glycaemic control on metformin alone.

High remnant-cholesterol levels increase the risk for end-stage renal disease: a nationwide, population-based, cohort study.

BACKGROUND: The effect of remnant-cholesterol (remnant-C) on incident end-stage renal disease (ESRD) has not been studied longitudinally. This retrospective cohort study evaluated the association between remnant-C and the development of ESRD in a nationwide Korean cohort. METHODS: Participants in a National Health Insurance Service health examination (n = 3,856,985) were followed up until the onset of ESRD. The median duration of follow-up was 10.3 years. The Martin-Hopkins equation was used to determine low-density lipoprotein cholesterol (LDL-C) levels from directly measured triglyceride, high-density lipoprotein cholesterol (HDL-C), and total cholesterol levels. Remnant-C levels were determined by subtracting HDL-C and LDL-C from total cholesterol. The risk for incident ESRD was calculated for each quartile of remnant-C, adjusting for conventional risk factors such as baseline renal function, comorbidities, and total cholesterol levels. RESULTS: ESRD developed in 11,073 (0.29%) participants. The risk for ESRD exhibited a gradual increase according to higher levels of remnant-C, with a 61% increased risk in the highest quartile than in the lowest (hazard ratio [HR] 1.61 [95% confidence interval (CI) 1.50-1.72]). The elevated risk for ESRD in the highest quartile versus the lowest quartile was more prominent in younger than in older subjects (20-29 years, HR 4.07 [95% CI 2.85-5.83]; 30-39 years, HR 2.39 [95% CI 1.83-3.13]; ≥ 70 years, HR 1.32 [95% CI 1.16-1.51]). In addition, the increased risk for ESRD related to higher remnant-C levels was greater in females than in males. CONCLUSIONS: Independent of conventional risk factors, remnant-C levels were positively associated with incident ESRD, particularly in younger populations and adult females. Reducing remnant-C levels may be a novel preventive strategy against ESRD.