Correlation of symptoms to serum vitamin D levels?

BACKGROUND AND OBJECTIVE: Recent studies have shown that vitamin D plays an important role in many disease processes. However, data is lacking which correlates the common symptoms attributed with vitamin D levels. This study was undertaken to find the correlation of symptoms and Vitamin D levels among ethnic Saudi Arabian population.

METHODS: A structured questionnaire was made and translated in the Arabic language, which included, age, weight and height, ethnicity and marital status. Patients who were visiting orthopaedic clinics for the first time were included after a detailed history, which ruled out any associated metabolic conditions. Patient's biometric data and the answering of the questionnaire were conducted by one of the senior members of the research group. The symptoms which were included in the questionnaire were fatigue, muscle cramps, joint and back pain, blood sugar levels, recurrent infections, hair loss, mood swings, weight gain, irritable bowel, fractures and history of malignancy. All the scores were graded between 1 and 9 (mildest 1 and severe 9) and only for fracture and malignancy it was yes/no answer. A score of ≤4 was accepted as no impact of the vitamin D levels on symptoms and answer of ≥5 was accepted as impact on the symptoms. Residents whose mother tongue was Arabic conducted all interviews. Blood was collected for 25 OHD levels, calcium and parathyroid hormone levels. Deficiency of vitamin D was defined as ≤20 ng/ml, insufficiency 21-29 ng/ml and normal level ≥30 ng/ml. The data was entered in the data base and analyzed using SPSS Inc Version 20.

RESULTS: Two hundred one patients completed the questionnaire but for final analysis the data of 187 was available for analysis as in 14 patients some of the data was missing. All were females and the average age was 55.9 ± 12.4 years, weight 78.9 ± 14.2 kg and height was 1.56 ± 7.01 m. The mean calcium level was 9.12 ± 0.33 mg/dl and, parathyroid hormone was 8.1 ± 6.06 pc/ml. The average 25 hydroxy vitamin D3 (25OHD) level was 21.8 ± 10.22 ng/ml. Forty-four (23.5%) of women had a normal vitamin D level, 51 (27.27%) had insufficiency and 92 (49.19%) had deficiency. Patients who complained of muscle cramps had 25OHD level of 18.86 ± 8.73 compared to patients who had no complains of cramps, 23.45 ± 9.2 ng/ml (p < 0.001) and symptom severity score (SSC) p value of p < 0.000. The results were similar for fatigue, Back pain, hair loss, mood swings and weight gain of P < 0.04, p < 0.07, p < 0.05, <0.03 and p < 0.09 for vitamin D levels and p < 0.001 for SSS. Forty-eight (25.6%) had a previous fracture in their history.

CONCLUSIONS: This study shows that many symptoms, which have been attributed to low vitamin D levels, are not true. Muscle Cramps, fatigue, mood swings, hair loss, back pain and weight gains appears to be more common in patients with low 25OHD levels.