A cautionary vitamin D tale?

A recent case report indicates that pharmacologic doses of vitamin D can cause hypercalcemia and hypervitaminosis D (Pediatrics 2012; 129: e1060-63).  The three cases all document good reasons for instituting therapy: craniotabes, hypocalcemic seizures, and tibial bowing.  The total dose that the patients received over 7-12 weeks ranged from 112,000 IU to 168,000 IU.  The ages of the patients ranged from 2 weeks to 33 months.   The peak abnormal calcium for all three patients was 11 mg/dL and the peak 25-hydroxy vitamin D was 102 ng/dL.  There were no clinical symptoms in these three patients due to increased calcium.  A fourth oh-by-the-way patient was described as well.  This patient was receiving vitamin D for an “inappropriate indication” (failure to thrive) and had received 3.6 million IU without monitoring.  This led to the development of a multitude of symptoms associated with a calcium level of 17.4 mg/dL.

My take-home points:

  • If giving generous doses of vitamin D, obtain a followup calcium several weeks into therapy. However, pharmacologic doses of vitamin D for valid indications pose a very low risk.
  • Excessive doses of vitamin D can be detrimental. (This last statement may be akin to the warning “hot coffee might cause a burn.”)

Related blog entries:

Common to be “D-ficient”

Vitamin D, IBD, and Causality

Live longer -drink more coffee

In a previous post, I was impressed with some of the benefits of coffee (Drink Up!).  More good news for coffee drinkers: drinking coffee is associated with decreased mortality (NEJM 2012; 366: 1891-1904).  Full disclosure –I don’t even drink coffee & I am not being paid by industry!

This study examined a huge population, 5,148,760 person-years (1995-2008) among 229,119 men and 173,141 women in the NIH-AARP Diet and Health Study with participants aged 50-71 at baseline.  With age-adjusted models, if adjusted for smoking, an inverse association between coffee consumption and mortality was noted.  With 6 cups per day, the hazard ratio (HR) was 0.90 for men and 0.85 for women.  For 2-3 cups, the HRs were 0.94 and 0.95 respectively.

Declines in mortality were noted for heart disease, respiratory disease, stroke, injuries/accidents, diabetes and infections, but not for deaths from cancer.  However, while coffee is associated with improved mortality data, a causal role for coffee consumption in reducing mortality cannot be established with this study.

Related link:

http://www.cnn.com/2012/05/16/health/coffee-drinking-longer-life/index.html?hpt=hp_t2

Oley: Check it out

Recently, I received a post from Oley Foundation (Linda May) asking me whether I was going to its convention.  While I am not, I did want to share that link:

http://www.oley.org/annualconf.html
The conference is in lovely Redono Beach, CA, right on the beach. We have miles of running paths, beautiful beaches, on site tennis courts, and swimming pool . To quote other MDs, “the Oley Annual conference is the most important clinical conference I attend all year…”

Also, Oley website is a good link for patients with enteral tubes, ostomies, and central lines. http://oley.org/

Many questions and how-to advice available.  For example, look at this link if interested in advice about swimming with central line, or enteral tube: http://www.oley.org/Swimming.html

Treating diabetes with surgery

Two articles in the New England Journal of Medicine point to the role of bariatric surgery in  treating type 2 diabetes in obese patients (NEJM 2012; 366: 1567-76 & 1577-85).  Type 2 diabetes looms as one of “the most challenging contemporary threats to public health.”

The first study was a randomized nonblinded single-center trial with 150 patients; mean BMI 36 with 34% having a BMI less than 35.  Intensive medical therapy was compared to Roux-en-Y gastric bypass or sleeve gastrectomy.  Mean patient age was 49 years. 42% of the gastric bypass group, 37% of the sleeve-gastrectomy group, and 12% of the medical treatment group achieved the primary end-point of a glycated hemoglobin level of ≤6% by the 12 month followup; the average starting glycated (HgbA1C) hemoglobin was 9.2%.  At the conclusion of the study, the average HgbA1C was 6.4, 6.6, and 7.5 respectively in the three groups.

The second study used a similar trial with 60 obese patients; all had BMI >35  At 2 years, diabetes remission occurred in 75% of their gastric bypass group, 95% of their biliopancreatic-diversion group and in no patients receiving intensive medical therapy patients. HgbA1C had similar rates of improvement as the 1st study: 6.3 in gastric-bypass, 4.9 in biliopancreatic-diversion group, and 7.7 in medical-therapy group.

While surgery has risks (see related material below), its benefits are likely to alter future treatment strategies with surgery being contemplated prior to exhausting all medical treatments.

Additional References:

  • -JAMA 2012; 307: 56-65.  Bariatric surgery and long-term cardiovascular events.
  • -JAMA 2011 [doi: 10.1001/jama.2011.817]). Large study failed to show that roux-en-Y gastric bypass prolonged life. n=850 VA pts to 41,244 controls. Same group showed no cost savings during initial 3 yrs: Med Care 2010; 48: 989-98.
  • -NEJM 2011; 365: 1365. Increased frequency of bariatric surgery in adolescents.
  • -NEJM 2009; 361: 445/520. perioperative safety.
  • -NEJM 2007; 357: 741, 753, 818. Bariatric surgery improves mortality rate.
  • NEJM 2007; 356: 2176. Review

Complications from surgery:

  • Early: bowel obstruction, DVT, GI bleed, leaks, pulmonary embolism, wound infection
  • After 30 days: anastomotic stricture, bowel obstruction, gallstones, dehiscence, fistula, Bleeding, Incisional hernia, nutrient deficiencies (iron, B12; calcium, Vit D (w RYGB), folate, B6/riboflavin).
  • Complications from gastric band: food impaction, erosion (now banned in Finland!), band slippage, gastric volvulus, band too tight, port infection
  • Roux-y gastric bypass:
    anastomotic leak 1.2%, anastomotic ulcers/stricture
  • Nutrient Monitoring–every 3months x 3, then yearly: Vitamin A, B12, Folate, Ceruloplasmin, Vit D-25OH, Iron studies, Zinc, thiamine, Selenium, Intact PTH, Mg, PT/PTT
  • Suggested supplements: Calcium c vitamin D 1200-2000mg, Iron at least 18-27mg/day, MVI with zinc/selenium
  • Also if duodenal switch, add Vitamin A 10,000 IU, and Vitamin D3 1200units daily or 50,000 units weeekly, Vitamin K 300 mcg,

Potential nutritional deficiencies:

  • B12, B6 (pyridoxine), Riboflavin (B2), B1 (Thiamine), Folate (B9)
  • Vitamins A,D,E, K
  • Calcium, Copper, Iron, Selenium, Zinc

Recommendations from NASPGHAN Post-Graduate Course 2011:

  • If post-op pain: epigastric –>do EGD & if neg do ‘RUQ w/u’, RUQ –> check U/S, LFTs possibly CT
  • If post-op vomiting –>do EGD
  • If post-op nausea –>Rx PPI and EGD if not improving
  • Anastomotic stricture in stomach –>dilate to 10-12mm in 1 session

Related blog posts (includes additional references)

Cardiovascular disease for the entire family

Staggering cost of obesity

A liver disease tsunami

Lower leptin with physical activity

Lower leptin with physical activity

Leptin is a cytokine expressed primarily by adipose tissue and helps regulate energy homeostasis in the body.  Higher leptin levels are found in obesity and associated with an increase risk of cardiovascular disease, insulin resistance, and type 2 diabetes.  In a recent study, physical activity, especially vigorous physical activity, has been shown to be negatively associated with leptin levels (J Pediatr 2012; 160: 598-603).

This study was conducted in school settings in 10 European cities from 9 countries (n=902) with ages 12-18 years.  Several fitness tests including handgrip, long jump, and shuttle runs were measured along with serum fasting leptin, insulin, and glucose.

Vigorous activity and fitness test results were associated with lower leptin levels; these findings were maintained when controlling for confounders.  It is not known the exact mechanisms whereby physical activity can lower leptin levels as this finding is independent of total body fat.  The authors note that previous studies have shown some contradictory results; the authors note that this could be related to drawbacks in how some studies measured physical activity.

This study’s information, when combined with previous studies (see below) on hormonal adaptations with weight loss, suggest a reason why exercise is important to maintain weight loss.  Losing weight without exercise could result in increased appetite and make it more difficult to achieve long-term results.  In contrast, physical activity may help maintain weight loss by improving hormonal adaptation.

Additional references:

  • -NEJM 2011; 365: 1597.  Persistence of hormonal adaptations with weight loss.  Due to persistent changes in hormones like leptin & peptide YY, hard to keep wt off -result is increased appetite.
  • -NEJM 2009; 360: 859.  Obesity-wt loss: composition of diet does not seem to be important.  Total calories important.
  • -NEJM 2007; 356: 237.  Leptin receptor deficiency present in 3% of 300 patients with early-onset obesity and hyperphagia.
  • -Pediatrics 2007; 120: suppl 4: S164-S287.
  • -NEJM 2007; 357: 370.  Obestiy spread in social network.
  • -Gastroenterology 2007; 132: 2085-2276.  Special issue on obesity issues.
  • -NEJM 2006; 355: 1593.  Case review on obesity c DDx and mgt.

Cardiovascular disease for the entire family

This month’s Journal of Pediatrics features an article for the entire family (J Pediatr 2012; 160: 590-7 [editorial pg 539]).  The authors demonstrate that children screened for cholesterol can serve as an index case for the entire family.  During a 26-year prospective followup of 852 pediatric patients (5-19 years old at enrollment) from Cincinnati, the authors assessed relationships of childhood risk factors with parental cardiovascular disease (CVD), type 2 diabetes (T2DM), and high blood pressure (HBP).

  • Pediatric HBP and low HDL cholesterol were predictive of parental CVD ≤age 50
  • Pediatric HBP and high triglycerides were predictive of parental CVD ≤age 60
  • Pediatric high triglycerides and high LDL cholesterol were predictive of parental CVD ≤age 66

The related editorial reviews large studies regarding lipid assessments, including the Bogalusa study with more than 3000 children and the Muscatine study with more than 14,000 children.  In addition, the editorial reviews the recommendations from an expert pediatric panel which suggested screening all children for dyslipidemia between 9 and 11 years. Interestingly, the editorial reviews the fact that screening for cholesterol has not been shown to harm children.  “The evidence is not sufficient to demonstrate any adverse affects.”

Although no harm has been proven, the expert recommendations do not have prospective data demonstrating benefit either.  While it is known that atherosclerotic lesions, including fatty streaks and calcifications, can develop in childhood, it is not known that current treatment strategies will improve long-term outcomes.  This study, however, provides an additional rationale for screening; namely, by identifying children with dyslipidemia, primary care providers can identify parents with cardiovascular disease who are more likely to benefit from urgent intervention.

Additional references:

  • http://hin.nhlbi.nih.gov/atpiii/calculator.asp?usertype=prof (cholesterol risk calculator)
  • Pediatrics 2011; 128 (suppl 5): S213-56.  Expert panel guidelines for cardiovascular health and risk reduction in children and adolescents.
  • -NEJM 2011; 365: 2078.  Use of statins to lower LDL to 60-70 range halted progression of coronary artery disease.
  • -Pediatrics 2007; 120: e189, e215.  US Preventive Services Task Force:  “the evidence is insufficient to recommend for or against routine screening for lipid disorders” up to age 20.  Consider pediatric drug Rx:
    1. After dietary failure
    2. LDL >190
    3. LDL >160 & FHx of CVD before age 55
    4. triglycerides >250-500 persistently
  • Pediatric Nutrition Handbook AAP Lipid types:type I -increased trig  (rare)
    type IIa -increased chol & LDL
    (most common)
       Homozygous: chol >500
         xanthomas before 10 yrs, vascular dz before age 20
       Heterozygotes with lower chol
    type IIb -elevated trig & chol/LDL
    (3rd most common)
    type III -abnormal LDL density (rare)
    type IV -elevated trig (2nd most common)
         may be increased with diabetes, obesity, inadequate fasting; may need to study parents to establish dx
    type V -increased trig/VLDL (rare)
         exclude nephrotic synd, hypothyroid, diabetes

Breastfed babies less likely to develop fatty liver

In a study presented at AASLD meeting (San Francisco, November 4, 2011), Ayonrinde et al followed 1170 children in Australia (www.rainstudy.org.au) from birth to age 17. Anthropometric measurements were followed regularly and a liver ultrasound was obtained at age 17.  Patients who reported consuming alcohol were excluded.

By age 17, 16% of girls and 10% of boys had developed nonalcoholic fatty liver disease (NAFLD). Breastfeeding was highly protective.  Infants breastfed for more than 6 months were less than half as likely to develop NAFLD.

As noted in this blog recently (A liver disease tsunami), fatty liver disease is a huge problem.  While this study may not influence the choice to breastfeed in many cases, it highlights yet another advantage of breastfeeding. 

Previous post on breastfeeding:

More evidence that breastfeeding improves cognitive development

Vitamin D, IBD, and Causality

The importance of vitamin D has been noted in this blog previously (Common to be “D-ficient” ).  Now a study implicates vitamin D as a risk factor for developing inflammatory bowel disease, especially for Crohn’s disease (Gastroenterology 2012: 142: 482-89).  It is known that vitamin D influences innate immunity.  As such, it may play a role in the susceptibility to Crohn’s disease (CD) and Ulcerative colitis (UC).

This prospective study included 72,719 women (age 40-73) enrolled in the Nurses’ Health Study.  Research subjects completed an assessment of diet and lifestyle along with 25-hydroxy vitamin D [25(OH)D] levels.  The 25(OH)D levels were predicted; this prediction was based on a validated model which included vitamin D intake, sun exposure, race, and body mass index (J Natl Cancer Inst 2006; 98: 451-9).  This model was validated against directly measured 25(OH)D levels.

During nearly 1.5 million person-years of followup, 122 incident cases of CD and 123 cases of UC occurred.  The adjusted hazard ratio (HR) for the highest quartile of 25(OH)D was 0.54 for CD and 0.65 for UC compared to the lowest quartile.  Compared with a level less than 20, the highest quartile HR was 0.38 for CD and 0.57 for UC.

In addition, the authors identified a significant inverse association between dietary supplemental vitamin D and UC; an insignificant reduction in CD risk was noted with dietary intake.  Although it is difficult to determine causality, these data convincingly show that ‘healthy’ levels of vitamin D are associated with a lower risk of IBD.

Staggering cost of obesity

For a single individual, the burden of obesity can be enormous; for a society, the projected costs for health and economics are hard to fathom (Lancet 2011; 378: 815-25).

By 2030, this report projects that there will be 65 million more obese adults in the US and 11 million more in the UK.  This is expected to cause an additional  6-8.5 million cases of diabetes, 5.7-7.3 million cases of heart disease/stroke, about 500,000 cases of cancer, and loss of 26-55 milion life years.  The medical costs are estimated to increase $48-66 billion/year in the US.

These projections are based on expected increases in the percentage of individuals who are obese.  In 2008, approximately 32% of US adult men were obese based on BMI; in 2030, the projected number is 50-51% for men.  Among US women: 35% in 2008 –> 45-52% in 2030.

To flatten the curve on spending, we will need to look at flattening other curves.

Additional references:

  • A liver disease tsunami
  • -NEJM 2011; 365: 1597. Persistence of hormonal adaptations with weight loss. Due to persistent changes in hormones like leptin & peptide YY, hard to keep wt off -result is increased appetite.
  • -NEJM 2009; 360: 859. Composition of diet does not seem to be important. Total calories important.
  • -Pediatrics 2007; 120: suppl 4: S164-S287.
  • -NEJM 2007; 357: 370. obestiy spreads in social network.  Your friends may be more influential than your genetics.
  • -Gastroenterology 2007; 132: 2085-2276. Special issue on obesity issues.
  • -NEJM 2006; 355: 1593. Case review on obesity c DDx and mgt.
  • -Pediatrics 2003; 112: 424. Position paper on prevention in childhood.
  • -Gastroenterology 2001; 120: 669-681. (review)
  • -J Pediatr 2005; 147: 429. TV viewing predicts adult BMI.
  • -Lancet 2001; 357: 505-8. One extra soda/day incr risk of obesity by 60%
  • -NEJM 1999; 341: 1097. BMI & mortality.

Common to be “D-ficient”

Many of the children that a pediatric gastroenterologist sees are at risk for Vitamin D deficiency, including children with inflammatory bowel disease, cystic fibrosis, celiac disease, and liver diseases.  In addition, vitamin D deficiency is widespread: in U.S. 50% of children aged 1-5 years and 70% 6-11 years are vitamin D deficient or insufficient. A thorough review on this “D-lightful” vitamin was in a recent JPEN (JPEN J Parenter Enteral Nutr 2012; 9S-19S).

History: In 1822 Sniadecki recognized children in urban but not rural Poland developed rickets. He postulated the effects of the sun as the reason for rickets; his idea was dismissed.  In 1920s, the concept of irradiating milk to prevent rickets emerged. In 1950s, outbreak of hypercalcemia in infants in Great Britain was thought to be related to vitamin D fortification and curtailed this practice in Europe.  However, these cases were likely due to Williams syndrome.

Sources of vitamin D: oily fish (salmon), cod liver oil, some mushrooms, egg yolk, & sunlight. Exposure of an adult in a bathing suit to one minimal erythemal dose (MED) is equivalent to ingesting 20,000 IUs of Vitamin D. (The minimal dose that induces any visible reddening at that point is defined as one MED.)

Effect of sunscreen: A sun protection factor (SPF) of 30 absorbs approximately 98% of solar ultaviolet radiation & thus lowers vitamin D production by 98%.

Ethnicity: Melanin is an effective SPF.  A person of african-american descent, on average, has an SPF of 15, which reduces vitamin D production by 90%.

Age: Aging decreases 7-dehydrocholesterol in human skin.  Due to this, the elderly produce much less vitamin D.  For example, a 70 year old has a 75% reduction compared to a 20 year old.

Forms of vitamin D:  25-hydroxyvitamin D (25OH-D) is the major circulating form of vitamin D & physicians measure 25OH-D. 25OH-D is metabolized in kidney to 1,25-dihydroxyvitamin D (1,25OH-D), also called calcitriol.  This is the most biologically-active and is responsible for increasing intestinal calcium absorption and mobilizing calcium from bone.  However, 1,25OH-D provides no information vitamin D deficiency; it can be elevated or normal in deficiency states.

  • Cholecalciferol (vitamin D-3) is formed in the skin from 5-dihydrotachysterol.
  • Ergocalciferol (Vitamin D-2) is the form in Drisdol (8000 IU/mL) & Ergocalciferol Capsules (1.25 mg =50,000 USP Units)

Vitamin D deficiency:  The exact numbers are debated.  The institute of medicine (IOM) has considered individuals deficient if 25OH-D is <20 ng/mL.  The Endocrine Society and the author suggest vitamin D deficiency as <20 ng/mL & insufficiency as <30 ng/mL.  The author recommends ideal levels between 40-60 ng/mL.

Consequences of deficiency:

Osteoporosis, Osteopenia, Rickets (see references below): Bone weakening occurs due to loss of phosphorus from the kidneys.  Vitamin D deficiency lowers accrual of calcium in skeleton and leads to osteoporosis, osteopenia, and rickets. Imaging for rickets: the best single radiographic view for infants and children younger than 3 years is an anterior view of the knee that reveals the metaphyseal end and epiphysis of the femur and tibia. This site is best because growth is most rapid in this location, thus the changes are accentuated.

Nonskeletal consequences: vitamin D deficiency is associated with increased risk for preeclampsia, URIs, asthma, diabetes (type 1), multiple sclerosis, hypertension, and schizophrenia.

Treatment:

  • Infants who are breastfed should be receiving supplemental vitamin D, 400 IU/day.
  • Adults/children (>1 year) RDA 600 IU/day –mostly from diet per IOM. Yet author states, “it is unrealistic to believe that diet alone can ….provide this requirement.”
  • In vitamin D deficient patients: (initial treatment) 2000 IU/day or 50,000 IU/week for 6 weeks.
Toxicity from vitamin D (from NEJM 2010; 364: 248-254.): “Toxicity from vitamin D supplementation is rare and consists principally of acute hypercalcemia, which usually results from doses that exceed 10,000 IU per day; associated serum levels of 25-hydroxyvitamin D are well above 150 ng per milliliter (375 nmol per liter). The tolerable upper level of daily vitamin D intake recently set by the Institute of Medicine (IOM) is 4000 IU.”

Additional references:

  • -Pediatrics 2008; 122: 398. Should give 400 IU/day to breastfed babies. Consequences of Vit D deficiency: increased risk for DM, multiple sclerosis, cancer (breast, prostate,colon), rickets, and schizophrenia. Article lists vit D content of foods (high in cod liver oil, shrimp, fortified milk, many fish). Severe deficiency when < 5ng/mL, deficient if < 15 ng/mL; probably should be >32 ng/mL. Causes of vit D deficiency: decreased synthesis (due to lack of sun -skin pigmentation, sunscreen/clothing, geography, clouds), decreased intake, decreased maternal stores & breastfeeding, malabsorption (eg celiac, CF, EHBA, cholestasis), increased degradation; treatment of rickets: double-dose of vitamin d (~1000 IU/day for babies & 5000 for older kids) x 3-4 months along with calcium (30-75/mg/kg/day). Follow Ca/phos/alk phos monthly. Alternatively, give ~100,000 units over 1-5 days.
  • -JPEN J Parenter Enteral Nutr. 2011;35:308-316-Results: The study included 504 IBD patients (403 Crohn’s disease [CD] and 101 ulcerative colitis [UC]) who had a mean disease duration of 15.5 years in CD patients and 10.9 years in UC patients; 49.8% were vitamin D deficient, with 10.9% having severe deficiency. Vitamin D deficiency was associated with lower HRQOL (regression coefficient –2.21, 95% confidence interval [CI], –4.10 to –0.33) in CD but not UC (regression coefficient 0.41, 95% CI, –2.91 to 3.73). Vitamin D deficiency was also associated with increased disease activity in CD (regression coefficient 1.07, 95% CI, 0.43 to 1.71). Conclusions: Vitamin D deficiency is common in IBD and is independently associated with lower HRQOL and greater disease activity in CD. There is a need for prospective studies to assess this correlation and examine the impact of vitamin D supplementation on disease course.
  • -JPGN 2011;53: 361. similar prevalence of low Vitamin D as general population –58% with less than 32.
  • -JPGN 2011; 53: 11. Guidelines for bone disease with inflammatory bowel disease.
  • -Pediatrics 2010; 125: 633. Increasing Vit D deficiency noted in minority children. n=290. 22% w levels <20, 74% <30.
  • -Hepatology 2011; 53: 1118. Good vitamin D levels are another favorable predictive factor in antiviral response to Hep C along with IL28B.
  • -NEJM 2010; 364: 248-254. Vitamin D insufficiency. Levels between 20-30 may be OK -not enough evidence to determine conclusively whether this level is detrimental
  • -J Pediatr 2010; 156: 948. High rate among african americans with asthma, 86%. n=63.
  • -Pediatrics 2009; 124:e362. n=6275. 9% of pediatric patients vit D deficient & 61% were insufficient.
  • -Pediatrics 2009; 124:e371. n=3577. low 25OH-D levels inversely assoc with SBP/metabolic syndrome.
  • -NEJM 2009; 360: 398. case report of rickets
  • -J Pediatr 2003; 143: 422 & 434
  • -Pediatrics 2003; 111: 908. 200 IU Vit D recommended for all breastfed infants.
  • -J Pediatr 2000;137: 153 & 143.. Nutritional rickets–primarily in blacks; rec vitamin D 400 IU per day.