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Darker skin pigmentation linked with lower serumvitamin D
concentrations
Darker skin pigmentation has been associated with lower serum vitamin D
concentrations, reports a single-centre, cross-sectional study.
B
ridget Kaufman, MD, of the Mount
Sinai School of Medicine, New York,
explained that vitamin D is a fat-solu-
ble vitamin that maintains skeletal health.
Deficiency of vitamin D has been impli-
cated in the development of numerous
conditions, including diabetes, autoim-
mune diseases, and cancer.
While some studies have found no associ-
ation between 25-hydroxyvitamin D levels
and skin phototype, others have demon-
strated lower levels in dark-skinned vs
fair-skinned individuals. This difference is
thought to be due to decreased ultravio-
let B absorption in individuals with higher
melanin content.
Dr Kaufman and colleagues aimed to fur-
ther elucidate the correlation between
vitamin D status and skin pigmentation in
subjects living in New York City. From 2015
to 2016, 124 subjects with Fitzpatrick Skin
Type I–VI were recruited.
Participants completed a questionnaire on
typical sun exposure, use of sun-protective
clothing and sunscreen, and vitaminD intake.
Physician assessment included Fitzpatrick
Skin Type determination and measurement
of skin pigmentation via spectrophotometry.
Blood was drawn to assess levels of serum
25-hydroxyvitamin D2 and D3.
All 124 subjects completed the study. The
majority (87.9%) were Fitzpatrick Skin Type
III–VI. AWilcoxon two- sample test was per-
formed to examine the median difference
in vitamin D concentration (ng/mL) between
patients with Fitzpatrick Skin Type I–III
(lightly pigmented) vs Fitzpatrick Skin Type
IV–VI (darkly pigmented) and showed sig-
nificant evidence of a difference between
groups (Z = 3.17, (P < 0.01).
Spearman correlation tests showed a neg-
ative correlation between serum vitamin
D concentration and spectrophotometer
measurement of skin pigmentation and a
positive correlation between serum vitamin
D concentration and average self-reported
vitamin D food intake.
Insufficient evidence of a difference in
serum 25-hydroxyvitamin D levels between
ethnic groups was available, low vs high
sun exposure, and low vs high use of sun
protection.
Dr Kaufman concluded that darker skin pig-
mentation is associated with lower serum
25-hydroxyvitamin D concentration. Serum
vitamin D level also appears to be related
to intake of vitamin D-rich foods and mul-
tivitamins containing vitamin D, but not
self-reported level of sun exposure or use
of sun protection.
Given that the study sampled primarily
individuals with Fitzpatrick Skin Type III–
VI, further research is needed in individuals
with Fitzpatrick Skin Type I–VI to evaluate
the association between skin pigmentation
and vitamin D status.
“The research,” Dr. Kaufman asserted, “car-
ries important implications in the prevention
and treatment of vitamin D deficiency in the
US. Research such as ours may help guide
clinicians and public health officials in man-
aging vitamin D deficiency.”
PracticeUpdate Editorial Team
Patients with haematologicmalignancies more likely to seek inpatient
oncodermatology consultation
Patients with hematologic malignancies are more likely than those with other cancers to seek an inpatient
oncodermatology consultation, finds a retrospective chart review.
G
regory Phillips, MD, of Memorial
Sloan Kettering Cancer Center, New
York, explained that dermatologic
conditions commonly arise in patients
undergoing treatment for cancer but have
not been systematically characterised, par-
ticularly in the inpatient setting.
Dr Phillips and colleagues sought to
describe the spectrum of skin diseases
encountered and the frequency of under-
lying malignancies requiring inpatient
dermatology consultations at their centre.
The charts of initial dermatology hospital
consultations over 2015 were reviewed.
Patients were identified through a query of
inpatient consultation notes and a consult
log. Relevant data were abstracted from
each patient’s electronic medical record
including demographics, reason for refer-
ral, dermatologic diagnosis, and primary
cancer diagnosis.
A total of 484 initial inpatient dermatology
consultations revealed 666 distinct der-
matologic diagnoses. Infections (n=149,
22.4%); inflammatory conditions (n=133,
20.0%); and drug reactions (n=99, 14.9%)
were the most common dermatologic
diagnoses.
The most common underlying malignancy
found was hematological (n=245, 50/6%),
followed by gastrointestinal (n=38, 7.9%);
and genitourinary (n=36, 7.4%).
Patients with breast cancer incurred a
greater burden of infectious diseases
(37.3%) and a lesser burden of inflamma-
tory conditions (13.7%) than patients with
other cancers (21.1% infection, 20.5%
inflammatory).
A higher frequency of skin drug reactions
was observed in gastrointestinal (12.1%) and
genitourinary (12.1%) cancer patients than
in other patients (6.3% nongastrointestinal,
7.4% nongenitourinary) patients.
Dr. Phillips concluded that inpatient derma-
tology consultations were most frequently
requested for patients with hematologic
malignancies. Infectious and inflammatory
skin conditions were the most common
reasons for inpatient referral for dermato-
logic evaluation in oncology patients.
The results may help identify underlying
malignancies that may present increased
risk of developing dermatologic conditions
requiring expertise of dermatologists for
diagnosis and management. The findings
reinforce the importance of inpatient onco-
dermatology collaboration in optimising
care of hospitalised cancer patients and
survivors.
PracticeUpdate Editorial Team
CONFERENCE COVERAGE
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PRACTICEUPDATE DERMATOLOGY