The COVID-19 pandemic in Greenland, epidemic features and impact of early strict measures, March 2020 to June 2022.

BackgroundThe COVID-19 pandemic was of major concern in Greenland. There was a high possibility of rapid transmission in settlements, and an increased risk of morbidity and mortality because of comorbidities in the population and limited access to specialised healthcare in remote areas.AimTo describe the epidemiology of the COVID-19 pandemic in Greenland and evaluate the effects of a strict COVID-19 strategy until risk groups were immunised.MethodsWe studied the epidemiology during March 2020 to June 2022. We describe the non-pharmaceutical interventions (NPIs), PCR-confirmed COVID-19 cases and vaccination coverage with data from the registries of the Greenlandic health authority.ResultsWe found 21,419 confirmed cases per 100,000 inhabitants (54% female, 46% male), 342 per 100,000 were hospitalised and 16 per 100,000 were admitted to the intensive care unit. The COVID-19 mortality rate was 39 per 100,000, all those affected were aged above 65 years. No excess overall mortality was observed. The vaccination coverage by June 2022 was 71.67 and 41% for one, two and three doses, respectively.ConclusionSARS-CoV-2 circulation in Greenland was low, given strict restrictions until all eligible inhabitants had been offered immunisation. The main impact of the pandemic was from May 2021 onwards with increasing numbers of confirmed cases. This occurred after introduction of the vaccine programme, which may have had an influence on the severity of the associated morbidity and mortality experienced. Halting community transmission of SARS-CoV-2 with NPIs until the majority of the population had been immunised was a successful strategy in Greenland.

Serum 25-hydroxyvitamin D, calcium and parathyroid hormone levels in Native and European populations in Greenland.

Ca homoeostasis is important to human health and tightly controlled by powerful hormonal mechanisms that display ethnic variation. Ethnic variations could occur also in Arctic populations where the traditional Inuit diet is low in Ca and sun exposure is limited. We aimed to assess factors important to parathyroid hormone (PTH) and Ca in serum in Arctic populations. We included Inuit and Caucasians aged 50-69 years living in the capital city in West or in rural East Greenland. Lifestyle factors were assessed by questionnaires. The intake of Inuit diet was assessed from a FFQ. 25-Hydroxyvitamin D (25OHD2 and 25OHD3) levels were measured in serum as was albumin, Ca and PTH. The participation rate was 95 %, with 101 Caucasians and 434 Inuit. Median serum 25OHD (99·7 % was 25OHD3) in Caucasians/Inuit was 42/64 nmol/l (25, 75 percentiles 25, 54/51, 81) (P<0·001). Total Ca in serum was 2·33/2·29 mmol/l (25, 75 percentiles 2·26, 2·38/2·21, 2·36) (P=0·01) and PTH was 2·7/2·2 pmol/l (25, 75 percentiles 2·2, 4·1/1·7, 2·7) (P<0·001). The 69/97 Caucasians/Inuit with serum 25OHD <50 nmol/l differed in PTH (P=0·001) that rose with lower 25OHD levels in Caucasians, whereas this was not the case in Inuit. Ethnic origin influenced PTH (ß=0·27, P<0·001) and Ca (ß=0·22, P<0·001) in multivariate linear regression models after adjustment for age, sex, BMI, smoking, alcohol and diet. In conclusion, ethnic origin influenced PTH, PTH response to low vitamin D levels and Ca levels in populations in Greenland. Recommendations are to evaluate mechanisms underlying the ethnic influence on Ca homoeostasis and to assess the impact of transition in dietary habits on Ca homoeostasis and skeletal health in Arctic populations.

Reliability of thyroglobulin in serum compared with urinary iodine when assessing individual and population iodine nutrition status.

The occurrence of thyroid disorders relies on I nutrition and monitoring of all populations is recommended. Measuring I in urine is standard but thyroglobulin in serum is an alternative. This led us to assess the reliability of studies using serum thyroglobulin compared with urinary I to assess the I nutrition level and calculate the number of participants needed in a study with repeated data sampling in the same individuals for 1 year. Diet, supplement use and life style factors were assessed by questionnaires. We measured thyroglobulin and thyroglobulin antibodies in serum and I in urine. Participants were thirty-three Caucasians and sixty-four Inuit living in Greenland aged 30-49 years. Serum thyroglobulin decreased with rising I excretion (Kendall's τ -0·29, P=0·005) and did not differ with ethnicity. Variation in individuals was lower for serum-thyroglobulin than for urinary I (mean individual CV: 15·1 v. 46·1 %; P<0·01). It required 245 urine samples to be 95 % certain of having a urinary I excretion within 10 % of the true mean of the population. For serum-thyroglobulin the same precision required 206 samples. In an individual ten times more samples were needed to depict I deficiency when using urinary I excretion compared with serum-thyroglobulin. In conclusion, more participants are need to portray I deficiency in a population when using urinary I compared with serum-thyroglobulin, and about ten times more samples are needed in an individual. Adding serum-thyroglobulin to urinary I may inform surveys of I nutrition by allowing subgroup analysis with similar reliability.

Forty-five year trends in overweight and obesity in an indigenous arctic Inuit Society in transition and spatiotemporal trends.

OBJECTIVES: Overweight and obesity associate with increased morbidity and premature death. Westernization of societies heralds rising obesity rates. A steep increase in body mass index (BMI) and overweight in Greenland from 1963 to 1998 led us to follow-up on height, weight, BMI, and rates of overweight among populations in Greenland and assess time trends between different stages of transition. METHODS: BMI was calculated from height and weight measured on Inuit and non-Inuit aged 50 through 69 years surveyed in 1963, 1998, and 2008 in Ammassalik district in East Greenland and in 1998 and 2008 in the capital Nuuk in West Greenland. RESULTS: A total of 1,186 were surveyed in 1963 (52 men/63 women), 1998 (309/226), and 2008 (297/239). BMI increased with time (P < 0.001; 1963/1998/2008 23.3/24.3/26.2 kg/m(2) ). In addition, BMI increased with urbanization in Inuit men (P = 0.001; settlements/town/city, in 1998, 23.9/24.9/25.5 kg/m(2) ; in 2008, 25.0/26.0/27.0 kg/m(2) ) while not in Inuit women (P = 0.18). The number of overweight Inuit (BMI >27 kg/m(2) ) increased with time in men (4.0/25.6/33.2% in 1963/1998/2008, P = 0.001) and in women (13.6/30.7/37.3%, P = 0.001). BMI was above 30 kg/m(2) in 2.0/10.8/17.5% of all Inuit men in 1963/1998/2008 (P = 0.003) and in 8.3%/23.0/24.5% of all Inuit women (P = 0.02) respectively. CONCLUSIONS: Overweight and obesity rates rise with time and with societal transition in Greenland. Settlements and town are catching up with the city where the rate of increase is diminishing, although there were gender differences.

The 1919-21 influenza pandemic in Greenland.

In Alaska, the 1918-20 influenza pandemic was devastating, with mortality rates up to 90% of the population, while in other arctic regions in northern Sweden and Norway mortality was considerably lower. We investigated the timing and age-patterns in excess mortality in Greenland during the period 1918-21 and compare these to other epidemics and the 1889-92 pandemic. We accessed the Greenlandic National Archives and transcribed all deaths from 1880 to 1921 by age, geography, and cause of death. We estimated monthly excess mortality and studied the spatial-temporal patterns of the pandemics and compared them to other mortality crises in the 40-year period. The 1918-21 influenza pandemic arrived in Greenland in the summer of 1919, one year delayed due to ship traffic interruptions during the winter months. We found that 5.2% of the Greenland population died of the pandemic with substantial variability between counties (range, 0.1% to 11%). We did not see the typical pandemic age-pattern of high young-adult mortality, possibly due to high baseline mortality in this age-group or remoteness. However, despite substantial mortality, the mortality impact was not standing out relative to other mortality crises, or of similar devastation reported in Alaskan populations.

Ethnicity influences BMI as evaluated from reported serum lipid values in Inuit and non-Inuit: raised upper limit of BMI in Inuit?

OBJECTIVE: To identify thresholds of BMI at which similar levels of serum lipids occur in Inuit and in non-Inuit as the impact of obesity on metabolic risk factors differ in Inuit compared to other ethnic groups. DESIGN: Published comparative data among Inuit and non-Inuit whites on BMI and HDL-cholesterol and triglyceride were identified for analysis. METHODS: A literature search was done for BMI, lipids, Inuit and Greenland or Canada. Studies with data on triglycerides and HDL-cholesterol in Inuit and non-Inuit Caucasians were selected and data were retrieved. MAIN OUTCOME MEASURES: Regression equations were computed for BMI and HDL-cholesterol and BMI and triglycerides. BMI for similar levels of lipids in Inuit and non-Inuit and ratios of Inuit/non-Inuit BMI's were calculated. RESULTS: At BMI 25 kg/m2 HDL-cholesterol was 1.7/1.6 mM in Greenland Inuit/non-Inuit women and 1.7/1.5 mM in men in a major comparative study. HDL cholesterol decreased by 0.09 for each 1 kg/m2 increase in BMI. Serum triglycerides were 1.0/1.1 mM for Greenland Inuit/non-Inuit women and 0.9/ 1.4 mM for men at BMI 25 kg/m2. Slopes were around 0.1. A comparative study in Canadian Inuit/non-Inuit gave similar results. The BMI levels required for similar HDL-cholesterol or triglycerides were around 27.5 kg/m2, and Inuit/non-Inuit BMI-ratios were around 1.1. CONCLUSION: The same degree of dyslipidaemia was seen when Inuit had a 10% higher BMI compared to non-Inuit. This may support the establishment of Inuit-specific BMI cut-offs for the purposes of health screening and population health surveillance.

Interpretation of TSH and T4 for diagnosing minor alterations in thyroid function: a comparative analysis of two separate longitudinal cohorts.

BACKGROUND: Minor alterations in thyroid function are frequent, and interpretation of thyroid function tests in the individual patient can be challenging. Furthermore, the choice of thyroid function test is debatable. To inform the debate, we performed a comparative evaluation of the variation in thyrotropin (TSH) and thyroxine (T4) in two different cohorts to illustrate the precision of TSH and T4 in the diagnosis and monitoring of thyroid dysfunction. METHODS: A comparative analysis of two separate longitudinal studies previously surveyed with monthly blood sampling for one year among 35 subjects. Participants were included based on T4 within the reference range and TSH either within (euthyroid; n = 15) or above (subclinical hypothyroidism; n = 20) the laboratory reference range on two independent blood samplings before inclusion. Exclusion criteria were known thyroid disease or use of thyroid interfering medication. TSH and T4 in individual samples were measured in a single batch to prevent between-batch variation. The distributions TSH and T4 were compared among euthyroid and subclinical hypothyroid individuals, and bootstrap estimates were used to calculate area under the curve (AUC). RESULTS: Collection of twelve, monthly blood samples in the 35 participants provided 420 samples, and data completeness was 100%. The mean TSH was 1.27/7.19 mIU/L and the mean total T4 was 106/85 nmol/L in euthyroid/subclinical hypothyroid participants. The subclinical hypothyroidism state deviated from the euthyroid by 20% for total T4 and by 466% for TSH. The overlap between the euthyroid and subclinical hypothyroid groups was 92.6% (389/420) for total T4 and 9.0% (38/420) of test results for TSH. The estimated AUC was 0.999 (95%-CI: 0.995; 1.00) for TSH and 0.853 (0.736; 0.935) for total T4. There was no confidence interval overlap between participant groups for TSH while there was a considerable overlap for total T4 (p < 0.001). CONCLUSION: The distributions of thyroid function tests illustrated how TSH outperforms T4 for detecting delicate differences in thyroid function in an individual. Thus, TSH was markedly better than T4 to discriminate between the subtle differences in thyroid function corroborating that TSH is the more sensitive and accurate index of thyroid function status in the individual patient.

Thyroid autoimmunity in Greenlandic Inuit.

Objective: This study aimed to provide the first data on the occurrence of thyroid autoimmunity among Inuit in Greenland, a distinct ethnic group who is not iodine deficient. Design: This study is a population-based cross-sectional study. Methods: Data were collected in Nuuk in West Greenland and in Ammassalik district in East Greenland. Information on lifestyle, diet and diseases was obtained using questionnaires. Thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb) and thyroid-stimulating hormone (TSH) were measured in serum. Iodine and creatinine were measured in spot urine samples. Results: The participation rate was 95% with 434 Inuit participants; 75% were smokers. Iodine excretion was 169 µg/24 h in urban West Greenland, 224 µg/24 h in the main town and 228 µg/24 h in settlements in rural East Greenland. TPOAb, TgAb or either of these was measured in the serum from 3.7, 5.9 and 8.3% of participants, respectively. TPOAb or TgAb was found in 9.3% of Inuit women and 7.5% of men and more frequently, in East Greenland Inuit with the higher iodine excretion (P = 0.02). There was some evidence suggesting that thyroid autoimmunity was more frequent among non-smokers (12.5%) compared to smokers (7.0%). Harbouring a thyroid autoantibody was most frequent in participants with TSH above 3.6 mIU/L (P < 0.001). Conclusion: Thyroid autoantibodies were rare among Greenland Inuit. While iodine nutrition was associated with autoimmunity similarly to other ethnic groups, the influence of sex and smoking was limited. This could suggest genetic component in Inuit, but the impact of cold, selenium and persistent organic pollutants needs to be elucidated.

Diagnosing dementia in the Arctic: translating tools and developing and validating an algorithm for assessment of impaired cognitive function in Greenland Inuit.

Background: The ageing Arctic populations raise the need for work-up of cognitive function that reflects language and cultural understandings.Aim: To translate and evaluate tools for work-up of cognitive impairment in Greenland.Methods: Step A: An expert panel was established to select tools suitable for the work-up of cognitive impairment at three different settings in Greenland. Step B: Tools were translated in a multiple-step process of independent translations with back-translation and adaptations by two independent translators and two Greenlandic physicians. Step C: a testing and validation process of the tools at three locations: the national hospital in the capital city; regional hospital in a town; health care centre in a small town.Results: Tools selected were Mini-Cog and RUDAS. Participants for testing of tools were 43 of 61 invited, of which six had dementia. RUDAS and Mini-Cog scores were associated (p < 0.001). The smoothed AUC was 0.87 (95%-CI, 0.65-0.95) for Mini-Cog and 0.90 (95%-CI, 0.76-0.97) for RUDAS. The sensitivity of Mini-Cog with a cut-off at ≤3 was 83.3%, and specificity was 62.2%. For RUDAS with a cut-off at ≤23, these were 100% and 75.7%, respectively.Conclusion: Requested tools have been translated for assessing cognitive function in the native Arctic setting. Small town residents with a Mini-Cog score of 3 or lower should be referred to a regional hospital for RUDAS, and a score of 23 or less should cause referral to the national hospital for a full work-up of cognitive function.

Adaptation to a High Iodine Intake in Greenland Inuit Suggested by Thyroid Disease Pattern.

Objective: Arctic living is influenced by cold winters, short summers, and excessive iodine intake from the traditional Inuit diet providing for habitation of the Arctic for centuries. This is changing and we surveyed thyroid function in populations living in Greenland. Design: Population-based cross-sectional study. Methods: Data were collected in the capital city in West Greenland and in rural East Greenland. Information on lifestyle, dietary habits, and medical history was obtained using questionnaires. Thyrotropin, free thyroxine, free triiodothyronine, thyroglobulin, and thyroglobulin antibody were measured in serum, iodine, and creatinine in spot urine samples. Results: One percent of the Greenlandic population was invited and 535 participated with an overall participation rate of 95%. Iodine excretion was 225 µg/24 hours in East Greenland and 169 µg/24 hours among West Greenland Inuit. Hyperthyroidism occurred in 10.7% of West Greenlandic Inuit (men/women: 4.3%/16.3%) and 7.8% of East Greenlandic Inuit (3.8%/12.8%). Hypothyroidism was found in 2.7% in West Greenland (0.0%/5.0%) and 5.6% (5.6%/5.6%) in East Greenland. Conclusion: Hyperthyroidism was frequent among Inuit and the occurrence of hypothyroidism was low. The pattern of hyper- and hypothyroidism among Greenlandic Inuit with adequate iodine intake was comparable with those seen in populations with iodine deficiency. Inuit may thus have adapted to excessive iodine intake over centuries, causing a need for a higher iodine intake to prevent iodine deficiency disorders.

[Health and healthcare in Greenland].

The Greenlandic society has changed rapidly within the last decades. Most of the population have good housing and access to clean water and sanitation. The neonatal and infant mortality is low, and the physical health of the children is good. Although tuberculosis is still common, lifestyle-related conditions and diseases are now of major public health importance. Sexual health has many challenges, and the suicide rate is extremely high. The healthcare system offers services on an international level, although huge distances and difficult access to advanced medical services is a challenge, which is discussed in this review.

[Vitamin D and Vitamin D-related diseases in Greenland].

Vitamin D has been associated with numerous diseases and is important for bones and muscle strength. The sources of vitamin D are dietary and endogenous. Shifts from the Arctic night to midnight sun influences endogenous production of vitamin D as does dietary transition in Greenland. Seasonal shifts in 25-hydroxyvitamin D (25-OHD) are 30%. In addition, dietary transition in Greenland has reduced 25-OHD intake to levels of concern in younger individuals. Disease pattern in Greenland mirrors those seen elsewhere, but there are indicators of genetic adaption to Arctic night and diet, which is discussed in this review.

Iodine in Edible Seaweed, Its Absorption, Dietary Use, and Relation to Iodine Nutrition in Arctic People.

Dietary iodine is important to human health, and both low and high iodine intake levels increase the risk of disease. Seaweed is rich in iodine and it is a common component in both Asian and in Arctic cuisines. While the intake and impact are known for Asian people, data are lacking for Arctic people. We aimed to (1) measure iodine content of dietary seaweeds in Greenland, (2) estimate iodine absorption, and (3) assess the impact on iodine intake in Arctic people. A hunter in East Greenland donated household seaweed for (1) measurement of iodine content and (2) ingestion of 45 g by each of eight individuals with subsequent urine collections. (3) In Ammassalik, 96% of 50-69-year-old Inuit reported on the frequency of intake of seaweed and provided a spot urine sample for iodine measurement. Seaweed species provided were Chondrus crispus and Ascophyllum nodosum. (1) The iodine content was 47 and 102 mg/g, respectively. (2) An estimated 1.1 and 1.9 mg of the ingested 2.1 and 4.6 of iodine in seaweed were excreted in the urine within 2 days. (3) More than two in three Inuit reported some dietary use, and 41% (109 of 268) reported a weekly intake of dietary seaweed, which was associated with iodine excretion. In conclusion, the iodine content of edible seaweeds in the Arctic is very high and bioavailable. Dietary intake contributed to the recommended iodine intake level, but marked variation in iodine excretion calls for evaluation of the impact on thyroid function.

Raised BMI cut-off for overweight in Greenland Inuit--a review.

BACKGROUND: Obesity is associated with increased morbidity and premature death. Obesity rates have increased worldwide and the WHO recommends monitoring. A steep rise in body mass index (BMI), a measure of adiposity, was detected in Greenland from 1963 to 1998. Interestingly, the BMI starting point was in the overweight range. This is not conceivable in a disease-free, physically active, pre-western hunter population. OBJECTIVE: This led us to reconsider the cut-off point for overweight among Inuit in Greenland. DESIGN AND FINDINGS: We found 3 different approaches to defining the cut-off point of high BMI in Inuit. First, the contribution to the height by the torso compared to the legs is relatively high. This causes relatively more kilograms per centimetre of height that increases the BMI by approximately 10% compared to Caucasian whites. Second, defining the cut-off by the upper 90-percentile of BMI from height and weight in healthy young Inuit surveyed in 1963 estimated the cut-off point to be around 10% higher compared to Caucasians. Third, if similar LDL-cholesterol and triglycerides are assumed for a certain BMI in Caucasians, the corresponding BMI in Inuit in both Greenland and Canada is around 10% higher. However, genetic admixture of Greenland Inuit and Caucasian Danes will influence this difference and hamper a clear distinction with time. CONCLUSION: Defining overweight according to the WHO cut-off of a BMI above 25 kg/m(2) in Greenland Inuit may overestimate the number of individuals with elevated BMI.