Patient Demographics (Table )
Between 1986 to 2007 the clinic saw a total of 95 patients with TG ≥ 20 mM at the time of first referral. The mean age ± standard deviation was 54.2 ± 11.9 years, with 70 patients (73.7%) being male and 75 patients (78.9%) Caucasian.
Demographic Information for HTG Patients At Initial Clinic Visit
History of Pancreatitis
Fifteen patients (15.8%) had a history of pancreatitis prior to referral to the clinic. Of these, the mean TG level at the time of non-acute presentation to the clinic was 38.13 mM [median 30.91 mM (IQ 25.6 - 52.2)], with the lowest referral TG level associated with prior pancreatitis being 20.5 mM (1815 mg/dl). Peak TG levels at the time of acute pancreatitis were not available for this analysis. Analysis of an additional cohort of 91 patients with TG levels between 10 and 20 mM (886 - 1771 mg/dl) at time of presentation to clinic revealed a history of pancreatitis in only 3 patients. In these 3, levels of TG at the time of acute pancreatitis were available, and all were > 20 mM (1771 mg/dl). As such, we conclude that pancreatitis is unlikely to occur as a result of hypertriglyceridemia unless TG are > 20 mM acutely.
Prevalence of dysglycemia (Table )
Thirty patients (31.6%) had a prior diagnosis of diabetes mellitus (DM). Of these, HbA1 c levels were not routinely available, however the majority (23/30) had poor control, with a mean FBS of 9.97 ± 4.37 mM (179 ± 79 mg/dL) at presentation to the clinic, and only 11 were on antihyperglycemic medication. An additional 5 patients (5.3%) were diagnosed with DM at their first clinic visit. Four new diagnoses of DM were made during the follow up period. In the entire group with severe hyperTG, 39 patients (41.0%) had a diagnosis of Type 2 DM by 2009. An additional 11 patients (11.6%) had impaired fasting glucose, giving a total of 50 patients (52.6%) having impaired glucose metabolism. At the latest visit, 82% of patients with a diagnosis of DM were taking antihyperglycemic medication.
Frequency of Diabetes and Elevated Fasting Blood Sugar (FBS) in HTG Clinic Patients
Other risk factors for hypertriglyceridemia and personal/family history of CVD (Table )
Dietary assessment by clinic dietitians was performed using three day food records plus a nutrient frequency questionnaire. Fat intake was considered high if >35% and carbohydrate intake high if >55% of total calories [7
]. Seventy-five patients (78.9%) had a diet high in fat and carbohydrates based on these criteria. Forty-two patients (49.4%) had no regular exercise. Alcohol consumption of >14 drinks/week or 7 - 14 drinks/week were recorded in 11 (11.6%) and 8 (8.4%) patients, respectively. Of the 15 (17.1%) patients previously diagnosed with hypothyroidism, 5 were inadequately controlled based on a TSH > 5 uIU/mL at presentation. No new diagnoses of hypothyroidism were made during follow up of this cohort. Twenty-four patients (25.3%) had smoked cigarettes within the past year. Sixteen patients (16.9%) were on beta-blockers, 6 (6.4%) were on estrogen therapy, 4 (4.3%) were on anti-retroviral therapy, and 3 (3.2%) were on a thiazide diuretic. Twelve patients (12.6%) had a personal history of coronary artery disease and 5 (5.3%) of peripheral vascular disease. Forty-seven patients (49.5%) indicated a history of premature vascular disease in first-degree relatives; only 15 (15.8%) were aware of other family members having dyslipidemia; however, this information was unknown to many patients.
Frequency of Risk Factors in HTG Patients at Initial Clinic Visit
Physical findings (Table )
Obesity, defined as a body-mass-index > 30 kg/m2, was present in 45 patients (47.4%), 57% of whom were previously diagnosed with diabetes. Overweight, as defined by a body-mass-index of 25-30 kg/m2 was present in an additional 29.5%, with only 23% of the cohort having a BMI less than 25 kg/m2. Eight patients (8.5%) presented with eruptive xanthomas, occurring with a range of TG levels of 20.5 - 171.9 mM, and a mean TG level of 67.8 mM [median 51.2 mM (IQ 27.55 - 97.85)]. Of these 8 patients, 2 were also felt to have lipemia retinalis (the only 2 of the entire cohort in whom this was noted, occurring at TG levels of 25.6 and 54.3 mM), 5 were obese, and 4 were diabetic. Three patients (3.2%) had palmar xanthomas. Corneal arcus was observed in 24 patients (25.3%). Three patients had abdominal tenderness at the initial visit, one of whom had a previous history of pancreatitis, and 6 were noted to have hepatomegaly.
Frequency of Clinical Findings in HTG Patients
Pre-Clinic and In-Clinic Treatment (Table )
At the initial visit 23 patients (24.2%) were taking a fibrate, with 17 on fibrate monotherapy, 4 on fibrate-statin, 1 on fibrate-niacin, and 1 on fibrate-omega-3 fatty acids (fish oil). Sixteen patients (16.8%) were referred taking statin monotherapy. Fifty-two patients (54.7%) were taking no hypolipidemic therapy, either due to lack of initiation or a history of lipid therapy intolerance. All patients received extensive dietary counseling and encouraged to limit dietary fats and simple carbohydrates as well as alcohol consumption. After the initial visit 80 patients (84.2%) were taking fibrate therapy, with 54 (56.8%) on fibrate monotherapy, 16 (16.8%) in combination with fish oil, 9 (9.5%) in combination with a statin, and 1 on fibrate-niacin combination. Eight patients (8.4%) were placed on fish oil monotherapy, while one was left on statin monotherapy. At the last visit recorded (84 patients), 56 patients (66.7%) remained on fibrate therapy, with 31 patients (36.9%) on monotherapy, 11 (13.1%) in combination with a statin, 4 (4.8%) in combination with fish oil, and 1 in combination with niacin. Six patients (7.1%) were on statin monotherapy, 3 (3.6%) on fish oil monotherapy, and 2 (2.4%) on niacin monotherapy. Of the remaining 25 patients, 17 (20.2%) were on combination therapy without a fibrate, and 8 (9.5%) were on no treatment.
Prevalence of Lipid-lowering Medications in Clinic HTG Patients
Laboratory and Anthropometric Values of Patients from Initial to Latest Visit (Table )
Triglyceride levels decreased from a mean of 35.04 ± 21.89 mM (3104 ± 1939 mg/dl) at the initial visit to 8.07 ± 8.71 mM (715 ± 772 mg/dl) at the latest visit (Figure ). Total cholesterol (TC) dropped from 12.8 ± 6.37 mM (495 ± 247 mg/dl) to 6.72 ± 2.73 mM (260 ± 106 mg/dl), and TC to high density lipoprotein cholesterol (HDL-C) ratio from 22.7 ± 25.59 to 6.70 ± 3.19 (Figure ). No statistically significant changes were detected for HDL-C. Average BMI was unchanged from first to the latest visit.
Triglycerides, Total Cholesterol, and Total Cholesterol:HDL-C Ratio at Initial and Latest Clinic Visit in HTG Patients. *, significant difference between means, p < 0.001 (two tail; pair student t-test).
Laboratory Values and Anthropometry of HTG Patients from Initial to Latest Visit