Plasma vitamin and mineral status in home parenteral nutrition patients

Home parenteral nutrition (HPN) provides long-term nutritional support for persons whose absorptive capacity is compromised by a variety of intestinal malabsorption problems. However, the presence of vitamin and mineral deficiency syndromes that normally would not have time to develop in the hospitalized patient receiving total parenteral nutrition has been reported in patients receiving HPN. This study entails a longitudinal survey of plasma concentrations of vitamins A, E, and 1,25-dihydroxyvitamin D, as well as the minerals zinc, copper, and selenium, in patients receiving HPN. Plasma samples from eight patients who had been on HPN for 1-92 months before the study began were obtained once a month over a 12-month period. The blood was drawn immediately before their evening infusion of TPN in order to approximate fasting plasma nutrient concentrations. Patient values were compared to fasting control values and to published norms. Values for vitamin A, 1,25-dihydroxyvitamin D, and zinc all were within the normal range, and there was no evidence of metabolic bone disease. Plasma vitamin E and copper concentrations exceeded the normal range for most of the 12-month period. Of all of the nutrients studied, only plasma selenium concentrations were consistently in the low-normal to below-normal range. Selenium levels in patients on HPN should be monitored regularly, and supplementation may be necessary if clinical conditions warrant.     

Water soluble vitamin requirements in home parenteral nutrition patients

Ascorbic acid, thiamin, niacin, pyridoxine, and folic acid status was evaluated in eight physiologically stable home parenteral nutrition patients. Six of these subjects received these vitamins as a twice weekly bolus and were studied over a period of 6 days. All vitamin levels were normal except for blood thiamin which was low, 72 h after each bolus. Since transketolase levels remained normal, this fall in blood thiamin probably had no functional significance. The urine excretion pattern of niacin and pyridoxine indicated normal metabolism and retention of these vitamins. Two patients, who required only parenteral fluid and electrolytes to remain weight stable, received none of these vitamins parenterally, but also maintained adequate vitamin status. These results suggest that in long term home parenteral nutrition patients these five vitamins can safely be given twice weekly, rather than daily, and that short bowel patients who maintain their weight without intravenous calories and protein also assimilate adequate amounts of these proximally absorbed water soluble vitamins from their diet.     

Plasma carnitine levels in patients receiving home parenteral nutrition

Patients on long-term home parenteral nutrition (HPN) are known to frequently develop hepatic steatosis or steatohepatitis. The etiology of this steatosis or steatohepatitis is unknown, but carnitine deficiency has been one of the postulated mechanisms. The importance of L-carnitine in hepatic fatty acid oxidation and the steatosis observed in primary and acquired carnitine deficiencies prompted us to determine plasma carnitine levels in 37 patients receiving long-term HPN. Thirteen patients (35%) had low total and free plasma carnitine levels. Fifteen of the 37 HPN patients were matched for age and sex with 15 patients with Crohn's disease who did not require HPN. Mean total and free plasma carnitine values were significantly lower (p less than 0.001) in these 15 HPN patients (32.2 +/- 11.9 and 28.4 +/- 10.8) when compared to Crohn's patients not requiring HPN (49.1 +/- 10.9 and 46.4 +/- 11.5). Associations were not detected between plasma carnitine and clinical or biochemical parameters that might have explained the low values.     

Plasma and red blood cell vitamin E status of patients on total parenteral nutrition

Plasma and red blood cell (RBC) tocopherol isomer (alpha, beta, delta, and gamma) concentrations were measured prior to, and following total parenteral nutrition (TPN), with Intralipid. Before feeding, nine of 13 patients had plasma total tocopherol levels less than 0.6 mg/dl (normal range 0.63-1.24 mg/dl) and 10 of 13 had total RBC tocopherol levels less than 0.2 mg/dl (normal range (0.20-0.39 mg/dl). Following 7 days TPN plasma vitamin E status increased significantly (p less than 0.001). However, this was due mostly to increases in the circulating level of beta + gamma-tocopherols. RBC vitamin E status was also significantly increased (p less than 0.001) following TPN, however, this was again due to incorporation of non-alpha-tocopherols. In a second study a alpha-tocopherol supplement, Vitlipid N, (9.1 mg alpha-tocopherol/day) was included in the feed. In these patients, large increases in plasma concentrations of non-alpha-tocopherol isomers were accompanied by an apparent improvement in alpha-tocopherol status (0.64 vs 0.44 mg/dl after 7 days). However, RBC alpha-tocopherol concentration did not change appreciably in these patients following either 7 or 14 days feeding. It is concluded that RBC vitamin E status is markedly influenced by the available plasma tocopherol pool and that provision of a small supplement of alpha-tocopherol is not sufficient to compete with the high concentration of non-alpha-isomers present in Intralipid. TPN utilizing fat emulsions containing high levels of non-alpha-tocopherol isomers (even when accompanied by alpha-tocopherol supplements) does not improve alpha-tocopherol status.     

Plasma vitamin levels in patients on prolonged total parenteral nutrition

Vitamins are essential in total parenteral nutrition (TPN), their importance being highlighted by repeated past documentation of various vitamin deficiencies particularly in patients on long-term parenteral nutrition therapy. This study evaluated the efficacy of water- (Soluvit) and fat-soluble (Vitalipid) vitamin supplementation in patients receiving total parenteral nutrition using the three in one 3-liter bag system. All patients received water-soluble vitamin supplements daily. Fat-soluble vitamin supplements were administered on a daily or twice weekly basis. Twenty-two patients were studied. In seven of the 22 patients vitamin status was assessed on more than one occasion during TPN support, thus bringing the total number of observations to 30. The mean duration of TPN support was 35 days. Eight of the observations were made during less than 10 days, three between 11-19 days, 15 between 20-60 days, and four during more than 60 days of TPN support. Biochemical deficiency as judged by subnormal enzyme activity or vitamin levels were present in 10% of the patients for thiamin, 3% for riboflavin, and 6% for nicotinic acid. By contrast 83% of the patients had low plasma vitamin C and B6 levels. Low plasma vitamin A and E levels were also present in 43 and 40% of the patients, respectively. According to the plasma concentrations of the vitamins studied it would appear that the commercial vitamin preparations used in this study are inadequate in maintaining optimal vitamin status.(ABSTRACT TRUNCATED AT 250 WORDS)     

Vitamin E and selenium status of patients receiving short-term total parenteral nutrition

In a prospective protocol, plasma tocopherols, selenium (Se), Se-dependent glutathione peroxidase, platelet aggregation and erythrocyte hemolysis were measured in 23 control subjects, and 15 patients receiving total parenteral nutrition (TPN), before and after 2 wk of TPN unsupplemented with vitamin E and Se. The results indicate that short-term TPN did not alter status of these nutrients. However, TPN patients had significantly lower plasma levels of Se (p less than 0.01) and alpha-tocopherol (p less than 0.01) relative to control subjects. Low plasma levels, with no attendant decrease in function, suggest a marginal depletion. In view of this, and considering the low amount of vitamin E and Se supplied by the TPN solutions, supplementation with these nutrients is recommended.     

Serum vitamin A and E concentrations in pediatric total parenteral nutrition patients

There is uncertainty as to optimal doses of fat soluble vitamins required by pediatric total parenteral nutrition (TPN) patients. We compared serum vitamin A (A) and E (E) concentrations analyzed by HPLC in chronic (greater than 2 weeks) TPN patients aged 1 month to 12 years to values obtained in out-patient surgery patients of the same age. TPN patients received 1500 micrograms of retinol and 2.5 IU of E as alpha-tocopheryl acetate (2.5 ml LyphoMed Multi Vitamin Concentrate). These doses were 214% of the recommended dose of A and 36% for E. Oral intake was minimal in most patients. The results of our study revealed a mean serum A level for TPN patients (N = 29) of 26.0 +/- 15.0 (SD) micrograms/dl vs 25.0 +/- 10.0 (SD) micrograms/dl in controls (N = 52). Mean serum E was 0.63 +/- 0.24 (SD) mg/dl vs 0.89 +/- 0.31 (SD) mg/dl for TPN patients and controls, respectively. There was no consistent trend related to duration of TPN for 23 patients with serial values. Seven (24%) TPN patients had serum A greater than mean + 2 SD of control (p less than 0.01). No values were less than mean - 2 SD. Infants on TPN had a significantly lower mean serum A (22.3 +/- 10.9 micrograms/dl) than TPN patients greater than 1 year of age (34.1 +/- 16.0 micrograms/dl; p less than 0.001). Fifty-two percent of TPN patients vs 26% of control had serum A less than 20 micrograms/dl (p greater than 0.1). For E, one patient had a high value and two patients low values relative to control.(ABSTRACT TRUNCATED AT 250 WORDS)     

Preparing patients for home parenteral nutrition

A comprehensive, interdisciplinary program for patients requiring home parenteral nutrition (HPN) is described. This program begins with an initial patient assessment, which includes medical prerequisites and evaluation of patient motivation and learning abilities, family supports, emotional status, and individual life-styles. The teaching phase involves instructing the patient in the tasks necessary to self-administer parenteral nutrition at home. Problems that can arise are presented, and patient self-monitoring for adverse reactions and problem solving is emphasized. Outpatient follow-up is provided by the interdisciplinary Nutrition Support Service in a clinic setting. Specific components of these visits in relation to physical and emotional adjustment to HPN are discussed. The Nutrition Support Service recognizes a long-term commitment to patients receiving HPN, and members of the team are available to assist patients when problems occur.     

Mortality in patients on home parenteral nutrition

Fifty out of 228 patients recorded on the U.K. Home Parenteral Nutrition Register have died. The earliest to die was at 10 days following the commencement of home parenteral nutrition (HPN), and the longest to die was after 5 1/2 years. Half of the patients who died, did so within 6 months of commencing HPN. Sixty % died of their underlying disease. Most patients with scleroderma or an underlying malignancy are dead within a year of commencing HPN. In contrast, patients with Crohn's disease or the short bowel syndrome due to volvulus do well. In only 14 patients was death attributable to the administration of HPN. In this group the main causes were septicemia, SVC thrombosis, and hepatic failure. Our study suggests that HPN should be used in patients with malignancy and scleroderma only in exceptional circumstances and that further work is necessary for the prevention of SVC thrombosis.     

Prevalence of vitamin D deficiency and response to oral vitamin D supplementation in patients receiving home parenteral nutrition

The purpose of this study was to document vitamin D status in home parenteral nutrition (HPN) patients and determine if oral vitamin D supplementation has a substantial effect. Methods: A retrospective chart review of eligible adults enrolled in the Southern Alberta Home Parenteral Nutrition program (n = 15) for a minimum of 6 months was conducted. Serum measurements of 25OHD were recorded and patients were categorized by vitamin D status as follows: sufficient; insufficient; deficient with respective levels of 25OHD ≥75 nmol/L, 27.5–75 nmol/L, and ≤27.5 nmol/L; and mixed. Results: Five of 15 patients had insufficient vitamin D status throughout the study period; all had short bowel syndrome. Nine were in the mixed category; 1 was consistently sufficient, and no one was consistently deficient. Patient demographics were similar between the insufficient and mixed groups. There were no significant differences in health outcomes between the insufficient and mixed vitamin D status groups. The median (interquartile range) dose and duration of vitamin D3 supplementation for the insufficient group was 5000 IU/d (4,000–7,143) for 1,175 (1,145–1,578) total days compared to 3,000 IU/d (1,000–7,143) for 1,529 (111–1,980) days for the mixed group. Conclusions: Most patients receiving HPN had insufficient vitamin D status. When prescribed high doses of oral vitamin D, patients did not consistently achieve appropriate 25OHD levels. Alternate routes of vitamin D supplementation in patients receiving HPN should be considered. Large multicenter prospective studies are needed to best characterize the relationship between vitamin D dosing for HPN patients and vitamin D status.     

Serum lipoproteins in home total parenteral nutrition patients

Patients maintained in our home total parenteral nutrition (HTPN) program receive very small amounts of cholesterol in their solutions. Because of the severe intestinal insufficiency which is characteristic of this group, they do not absorb significant amounts of cholesterol or bile salts from their intestines. We investigated the serum lipoproteins in nine patients maintained on HTPN for 36 +/- 4 (mean +/- SEM) months. Fat emulsions were given twice a week as a source of essential fatty acids. Mean serum cholesterol 110 +/- 6.5 mg/dl, LDL-cholesterol 75 +/- 6 mg/dl, and HDL-cholesterol 29 +/- 1 mg/dl, were at or below the 5th percentile compared with age- and sex-matched Lipid Research Clinic controls. HDL-cholesterol to serum cholesterol ratio was in the normal range (0.25 +/- 0.30). The mean serum cholesterol did not rise, but the mean serum triglyceride rose significantly from 72 +/- 4 to 104 +/- 16 mg/dl (p less than 0.05) immediately after completion of TPN infusions with fat emulsions. There was a negative correlation between the length of HTPN therapy and the total serum cholesterol (r = 0.43, p less than 0.05). Thus, HTPN patients have markedly depressed concentrations of total serum cholesterol, LDL-cholesterol, and HDL-cholesterol, but the ratio of HDL cholesterol to total serum cholesterol is in the normal range.     

Selenium status in patients receiving home parenteral nutrition

Selenium (Se) status was evaluated in patients with intestinal failure requiring home parenteral nutrition (HPN). Ninety-two percent of patients (11 of 12) studied just prior to starting HPN had low serum Se values, and the mean value was 42 ng/ml, significantly less than mean values in disease controls with Crohn's disease not on HPN (76 ng/ml) and healthy controls (88 ng/ml). Eighty-five percent of patients (22 of 26) already on HPN for 2 to 109 months when studied had low serum Se levels (mean 38.4 ng/ml). The mean 24-hr urinary Se values were 3.7 micrograms in patients on HPN who did not have Crohn's disease, 10.9 micrograms in HPN patients with Crohn's, and 17.9 micrograms in healthy controls. In patients with Crohn's disease on HPN, a significant direct correlation existed between serum Se and the activity of whole blood glutathione peroxidase, a selenoprotein ; and a significant inverse correlation was found between serum Se and months of HPN. This study confirms that Se deficiency is very common in patients before starting and during HPN. These data and recent reports of cardiomyopathies associated with Se deficiencies in patients on HPN increase the importance of proper Se replacement and maintenance.     

Effects of selenium supplementation on immune parameters in gut failure patients on home parenteral nutrition.

The relationships between some parameters of the immune response and selenium were investigated in five patients receiving home parenteral nutrition for short-bowel syndrome. They were first submitted to a relative depletion by providing 20 micrograms selenium/day as L-selenomethionine for 1 mo. Then, daily selenium intake was raised to 200 micrograms for 2-4 mo. On entering the study, the patients presented a relatively good health status, and immunological parameters were at the lowest limit of the normal range. Four patients rapidly responded to the 200-micrograms supplementation by a continuous increase in their plasma selenium levels, whereas the fifth patient showed a moderate and late increase. At the end of the trial, there was an improvement in the lymphocyte response to pokeweed and phytohemagglutinin mitogens in four patients and to CD3 in three patients. The response to two of three antigens (Candidin, Varidase) tested was also enhanced in the same patients, but the response to the third antigen (tetanus toxoid) was uniformly low in all patients. The only patient showing essentially no immune improvement after selenium supplementation was the one with a low and delayed increase in plasma selenium. This study supports a role for selenium in the maintenance of an optimal immune response in humans.     

Serum vitamin E levels in very low-birth weight infants receiving vitamin E in parenteral nutrition solutions

Serum vitamin E levels were measured in 17 very low-birth weight infants in the first 2 wk of life, before and after the institution of intravenous vitamin E supplementation in a dosage of 4.5 mg/day, as a component of MVI Pediatric multivitamin preparation. Serum vitamin E levels were 0.22 +/- 0.16 (SD) mg/dl before supplementation, and rose to 2.55 +/- 0.65 (SD) mg/dl in nine infants more than 899 g birth weight, and rose to 3.68 +/- 0.70 (SD) mg/dl in six infants less than 900 g at birth. These postsupplementation serum vitamin E levels are in the range in which a reduction of incidence or severity of retinopathy of prematurity and intraventricular cerebral hemorrhage has been reported by others. No toxic effects of the preparation or of the increased vitamin E levels were found.     

Vitamin D deficiency in patients receiving home parenteral nutrition

Background: In addition to its role in bone metabolism, vitamin D has important immunomodulatory and antineoplastic effects. Patients on home parenteral nutrition (HPN) receive most of their vitamin D from intravenous (IV) supplementation. Vitamin D deficiency is common in the general population, and the adequacy of vitamin D supplementation in HPN patients is unclear. The purpose of this study is to determine the vitamin D status of patients on HPN. Methods: Consecutive patients seen in a regional home nutrition program had their oral and IV vitamin D intakes determined. Plasma 25‐hydroxyvitamin D levels were measured in all patients. Intake of calcium, magnesium, and phosphate were also determined. Results: The mean 25‐hydroxyvitamin D level in 22 patients receiving HPN for a mean of 33.5 months (range, 1–177) was 42 nmol/L. Vitamin D deficiency was present in 15 (68%) patients and vitamin D insufficiency in 6 (27%) patients. The mean dietary vitamin D intake was 79.5 IU per day, while the mean IV supplementation was 166 IU per day. Conclusions: In this study of a regional Canadian HPN program, there was a high prevalence of vitamin D deficiency/insufficiency affecting virtually all patients. All patients receiving HPN should be supplemented with vitamin D and have their 25‐hydroxyvitamin D levels monitored. Further studies are required to determine optimal methods and dosing of vitamin D replacement using oral supplements or ultraviolet light therapy.