Hematologic abnormalities in adolescents who take oral contraceptive pills

Rare presentation of iron deficiency anaemia with cerebral venous sinus thrombosis in a middle-aged woman

This is a case of a female patient presented with a mild headache associated with recurrent episodes of nausea and vomiting, confusion and right-sided hemiparesis, diagnosed of haemorrhagic venous infarction from the thrombosis of left transverse and sigmoid sinus and probably the left vein of Labbe. She had severe microcytic hypochromic anaemia due to iron deficiency, without any other risk factors for cerebral venous thrombosis such as trauma history, infections, coagulation disorders or autoimmune diseases. She had a good prognosis after iron supplementation and anticoagulation therapy.

Association Between Anemia and Cerebral Venous Thrombosis: Case-Control Study

BACKGROUND AND PURPOSE

Anemia is often considered to be a risk factor for cerebral venous thrombosis (CVT), but this assumption is mostly based on case reports. We investigated the association between anemia and CVT in a controlled study.

METHODS

Unmatched case-control study: cases were adult patients with CVT included in a single-center, prospective database between July 2006 and December 2014. Controls were subjects from the control population of the Multiple Environmental and Genetic Assessment of Risk Factors for Venous Thrombosis (MEGA) study. Anemia was defined according to World Health Organization criteria: nonpregnant women hemoglobin<7.5 mmol/L, pregnant women<6.9 mmol/L, and men<8.1 mmol/L. We used logistic regression analysis, adjusting for age, sex, malignancy, oral contraceptive use, and pregnancy/puerperium.

RESULTS

We included 152 cases and 2916 controls. Patients with CVT were younger (mean age, 40 versus 48 years) and more often women (74% versus 53%) than controls. Anemia was more frequent in cases (27.0%) than in controls (6.5%; P<0.001). Anemia was associated with CVT, both in univariate analysis (odds ratio, 5.3; 95% confidence interval [CI], 3.6-7.9) and after adjustment for potential confounders (adjusted odds ratio, 4.4; 95% CI, 2.8-6.9). Hemoglobin as a continuous variable was inversely associated with CVT (adjusted odds ratio per 1 mmol/L change 0.53; 95% CI, 0.42-0.66). Stratification by sex showed a stronger association between anemia and CVT in men (adjusted odds ratio, 9.9; 95% CI, 4.1-23.8) than in women (3.6; 95% CI, 2.1-6.0).

CONCLUSION

Our data suggest that anemia is a risk factor for CVT.

Effect of hormonal contraceptives on vitamin B12 level and the association of the latter with bone mineral density

BACKGROUND

The study was conducted to estimate the effect of depot medroxyprogesterone acetate (DMPA) and oral contraceptives (OC) containing 20 mcg ethinyl estradiol on serum B12 and whether observed changes impact bone mineral density (BMD).

STUDY DESIGN

Serum B12 and BMD at the lumbar spine and femoral neck were measured on 703 women using OC, DMPA or nonhormonal (NH) birth control at baseline and every 6 months thereafter for 3 years.

RESULTS

OC and DMPA users experienced greater decreases in B12 than NH users (p<.001). A sharp decrease in B12 was observed during the first 6 months of hormonal contraceptive use (OC: 97 pg/mL and DMPA: 64 pg/mL) in contrast to 14 pg/mL among NH users (20%, 13% and 3% of their baseline values, respectively). Over the following 30 months, B12 levels of OC users remained almost flat, while DMPA users had a further 22-unit decrease. Very few women demonstrated B12 deficiency. Moreover, B12 levels were not associated with BMD.

CONCLUSION

Hormonal contraception causes B12 levels to decrease, but this does not appear to be clinically significant or affect BMD.

Oral contraceptives did not affect biochemical folate indexes and homocysteine concentrations in adolescent females

OBJECTIVE

The study was designed to determine the impact of currently available oral contraceptive agents (OCAs), smoking, and alcohol on biochemical indexes of folate and vitamin B-12 in adolescent females.

DESIGN

Subjects completed a 3-day weighed food record along with a detailed lifestyle questionnaire that included questions on OCA, cigarette, and alcohol use. After subjects had fasted overnight, blood samples were collected and analyzed for levels of serum and red blood cell (RBC) folate and serum B-12 and homocysteine.

SUBJECTS/SETTINGS

Two hundred twenty-nine adolescent females (aged 14 to 20 years) were recruited from southern Ontario, Canada, by advertisements in newspapers, high schools, universities, shopping malls, adolescent drop-in centers, and community groups.

STATISTICAL ANALYSES PERFORMED

Multiple regression models were used to determine the effect of lifestyle factors and covariates (e.g., dietary folate intake, supplemental folate intake, and age) on biochemical indexes.

RESULTS

OCA use, alcohol use, and smoking were not significantly associated with lower serum or RBC folate levels, after controlling for folate intake. Serum homocysteine levels were not associated with smoking or OCA use; however, we estimated a 13% higher concentration among alcohol users than nonusers. Smoking and alcohol use were not associated with serum B-12 levels, but OCA use was associated with an estimated 33% lower serum B-12 level than nonuse.

APPLICATIONS

Our findings provide no evidence to suggest that currently available OCAs have a negative impact on the folate status of adolescent females; thus, dietary advice designed to specifically encourage an increase in folate intake among adolescents who use OCAs is not supported. In contrast, serum B-12 levels were lower among OCA users than nonusers, which suggests that an interaction between OCA and some vitamins may persist. The suboptimal biochemical folate indexes of smokers may have more to do with the dietary quality of smokers than previously appreciated. Thus, efforts to improve dietary folate intakes of adolescents who smoke may be an important strategy for improving the folate status of young women.

Multivitamin supplementation in oral contraceptive users

The effects of oral contraceptives (OC) containing 30 micrograms of ethinyl oestradiol and of subsequent multivitamin and folic acid supplementation on vitamin A, total B2 [including its three individual constituents, i.e. riboflavine, RB; flavine-mono-nucleotide, FMN; and flavine-adenine-dinucleotide, FAD], B12, C and folate concentration in serum and red blood cells have been studied in a group of 59 non-pregnant female volunteers. The group taking OC comprised 28 women while 31 women were included in the group of non-OC users serving as the controls. The women were studied for four cycles. Blood samples were taken on days 3 and 23 of the first cycle to obtain baseline values of each analyte. Multivitamin and folic acid supplementation started on day 1 of the second cycle and this was continued daily throughout three consecutive cycles until the end of the study. Vitamin A levels were significantly higher and vitamin B12 levels were significantly lower in the group using OC. Comparison of the baseline values of vitamin total B2, FAD, C, serum and red blood cell folate as determined on days 3 and 23 of the first cycle of the two groups compared revealed no significant differences. Multivitamin and folic acid supplementation did not affect the concentrations of vitamin A and vitamin B12 with either group, whereas all other vitamins increased significantly in both groups. The consistency of each effect of multivitamin supplementation between the two groups was also tested. The degree of these effects was not statistically different between both groups. The results suggest that the vitamin status is indeed affected by OC treatment, but the effects of multivitamin supplementation are not different in OC and non-OC users. Supplementation during OC use or just after discontinuing treatment cannot be justified for healthy young women. However, in the case of women with a critical vitamin balance or higher folate needs, multivitamin supplementation may be considered.

Iron status of adolescent female athletes

To determine whether or not adolescent female athletes were more in need of routine dietary iron supplements than their nonathlete peers, the iron status of 32 athletes and 31 nonathletes was assessed. The athletes were track-team members in the middle of their season. Hemoglobin, transferrin saturation, and serum ferritin were evaluated, as well as the amount of dietary iron intake. Athletes had significantly lower serum ferritin levels and transferrin saturation (less than 16%) than did nonathletes. Black girls were significantly lower than whites on all three values. There were also a greater number of black girls deficient in serum ferritin. We conclude that athletes may be at greater risk for iron deficiency and, therefore, for iron deficiency anemia; and black adolescents may have an increased prevalence of iron deficiency, with black female athletes being at potentially greater risk for iron deficiency and its possible consequences. We recommend a more sensitive assessment of iron status in female athletes.

Iron deficiency in black females during late adolescence

The role of serum ferritin (SF) in detecting early iron deficiency and the associated risk factors in black adolescent females are evaluated. SF less than or equal to 12 ng/mL indicated low iron stores and a Hb less than or equal to 11.3 g/dL (5% ile for black females-Hanes Survey) anemia. Of the 103 females (means = 16.8 yr) screened in a Family Planning Clinic (FPC), 20.4% (21/103) had a low SF. Of these 21, 72% had a Hb greater than 11.3 g/dL. Chronologic age, gynecologic age, history of pregnancy, Tanner stage IV and V, and birth control method did not appear to be risk factors. However, longer rather than shorter use of oral contraceptives appeared to protect against iron deficiency. This study suggests that routine screening of iron status by hemoglobin and serum ferritin is warranted during annual FPC visits.