An approach to assess and adjust for the influence of multicollinear covariates on metabolomics association patterns-applied to a study of the associations between a comprehensive lipoprotein profile and the homeostatic model assessment of insulin resistance

Introduction Comprehensive lipoprotein profiling using proton nuclear magnetic resonance (NMR) spectroscopy of serum represents an alternative to the homeostatic model assessment of insulin resistance (HOMA-IR). Both adiposity and physical (in)activity associate to insulin resistance, but quantification of the influence of these two lifestyle related factors on the association pattern of HOMA-IR to lipoproteins suffers from lack of appropriate methods to handle multicollinear covariates. Objectives We aimed at (i) developing an approach for assessment and adjustment of the influence of multicollinear and even linear dependent covariates on regression models, and (ii) to use this approach to examine the influence of adiposity and physical activity on the association pattern between HOMA-IR and the lipoprotein profile. Methods For 841 children, lipoprotein profiles were obtained from serum proton NMR and physical activity (PA) intensity profiles from accelerometry. Adiposity was measured as body mass index, the ratio of waist circumference to height, and skinfold thickness. Target projections were used to assess and isolate the influence of adiposity and PA on the association pattern of HOMA-IR to the lipoproteins. Results Adiposity explained just over 50% of the association pattern of HOMA-IR to the lipoproteins with strongest influence on high-density lipoprotein features. The influence of PA was mainly attributed to a strong inverse association between adiposity and moderate and high-intensity physical activity. Conclusion The presented covariate projection approach to obtain net association patterns, made it possible to quantify and interpret the influence of adiposity and physical (in)activity on the association pattern of HOMA-IR to the lipoprotein features.publishedVersio

Pärjäin – tiennäyttäjä kansalaisen hyvinvointipolulla?

Kansalaisen on joskus vaikea löytää eri toimijoiden palveluvalikoimasta niitä palveluita, jotka vastaavat juuri hänen tarpeisiinsa. Tarvitaan uudenlaisia ratkaisumalleja, jotta henkilökohtaisuus, aika‐ ja paikkariippumattomuus, kansalaisten erilaiset kyvyt sekä uuden teknologian tuomat mahdollisuudet voidaan ottaa paremmin huomioon. Tekesrahoitteisessa OmaHyvinvointi‐hankkeessa (OHV) aikaisemmin kehitettyä Pärjäin‐konseptia sovelletaan ja kehitetään edelleen EAKR‐rahoitteisessa Pumppu‐hankkeessa kohti käytännön hyvinvointinavigaattoria, kansalaisen omaksi, arjen hyvinvoinnin tukijaksi.Tässä artikkelissa on tarkoituksena kuvata Laurea‐ammattikorkeakoulussa tehtyjä selvityksiä iäkkäiden ihmisten ITvalmiuksista, palvelutarpeista ja haasteista sekä IT‐pohjaisista interventioista ja Pärjäin‐tyyppisen sovelluksen mahdollisuuksista toimia sydänpotilaan hoitopolun tukena. Tavoitteena on tuottaa tietoa kansalaisen arjen elämää helpottavien palveluiden ja teknologioiden kehittämistyöhön.Kohderyhminä ovat iäkkäät eläköityvät ja sydän‐ ja diabetespotilaat Länsi‐Uudellamaalla ja tutkimusympäristönä Pumppu‐hanke. Pumppu–hanke on ylimaakunnallinen Euroopan Aluekehitysrahaston osittain rahoittama (EAKR) hanke, jossa kehitetään kansalaislähtöisiä, monitoimijaisia hyvinvointipalveluja.Tässä artikkelissa esitellään kolmen erillisen opinnäytetyön tuloksia, joiden aineistot on kerätty kyselytutkimuksena, kirjallisuuskatsauksena sekä fokusgroup‐haastatteluna ja analysoitu kuvailevalla tilastollisella analyysillä sekä sisällönanalyysillä.Tulosten mukaan iäkkäät henkilöt suosivat edelleen paperidokumentteja, vaikka merkkejä asennoitumisen muuttumisesta on nähtävissä nuoremmilla eläköityvillä vastaajilla. Mikäli sähköisiä palveluita käytettäisiin, olisi toivotuin väline tietokone ja tiedonsaantimuoto oma sähköpostitili. Sydänpotilaat kokivat hoitonsa pirstaleiseksi ja tiedonkulun puutteelliseksi. Ajatukset Pärjäin–tyyppisestä navigaattorista arjen apuna olivat myönteisiä niillä, jotka olivat tottuneita tietokoneen käyttöön. Oma osaaminen huoletti erityisesti tietokoneen käyttöön tottumattomia. Kirjallisuuskatsauksessa analyysin mukaan kansalaiset, jotka asuivat etäällä palveluista, kokivat etäkonsultaatiomenetelmien parantavan terveyspalvelujen saatavuutta ja tuottivat myös organisaatioille kustannussäästöjä

Serum fatty acid and lipoprotein subclass concentrations and their associations in prepubertal healthy Norwegian children

Introduction The lipid metabolism is one of the most important and complex processes in the body. Serum concentrations of 18 fatty acids (FAs) and 24 lipoprotein features, i.e. concentrations of lipoprotein main and subclasses and average particle size in main classes, in 195 ethnic Norwegian children from the rural Fjord region were quantified by chromatography. Objectives To assess gender differences in prepubertal children and reveal predictive FA patterns for lipoprotein features. Methods Lipoprotein features were modelled from FA profiles using multivariate regression. Results Contrary to observations for adults from the same region, gender differences in prepubertal children were generally small. However, higher concentrations of C16–C18 FAs for girls compared to boys correlated to higher concentrations of triglycerides (TG) and very low density lipoprotein (VLDL) particles and larger average size of VLDL particles. Concentrations of high density lipoprotein (HDL) and its subclass of medium particle size were higher in boys than in girls. These findings are opposite to observations in adults from the same region, but reflect that prepubertal boys are more physically active than girls. Furthermore, children possessed only half the serum levels of eicosapentaenoic acid and docosahexaenoic acid measured in adults. Since sampling was done after 12 h of fasting, these differences may reflect higher rate of utilization of these crucial FAs in children. Conclusion Good predictive models were obtained for TGs, VLDL and chylomicrons with C14–C18 FAs as major contributors. Weak predictive associations were observed for HDL and Apolipoprotein A1 (ApoA1) with C20–C24 FAs as contributors.publishedVersio

Predictive associations between serum fatty acids and lipoproteins in healthy non-obese Norwegians: implications for cardiovascular health

A battery of methods for multivariate data analysis has been used to assess the associations between concentrations of fatty acids (FAs) and lipoprotein subclasses and particle size in serum for a normolipidemic population of ethnic Norwegians living in the rural Fjord region. Significant gender differences were found in the lipoprotein and FA patterns. Predictive FA patterns were revealed for lipoprotein features of importance for cardiovascular (CV) health. Thus, the subclasses of atherogenic small and very small low density lipoprotein (LDL) particles and the same subclasses of high density lipoprotein (HDL) particles were associated with a pattern of saturated FAs and mono-unsaturated C16-C18 FAs. Eicosapentaenoic acid (EPA) and the ratio of EPA to arachidonic acid (AA) had strongest associations to features that promotes CV health: (i) large average size of HDL and LDL particles, and, (ii) small average size of very low density lipoprotein (VLDL) particles. Total concentration of HDL in both genders correlated to EPA, but docosahexaenoic acid (DHA) correlated just as strongly for women. For men, docosapentaenoic acid (DPA) showed stronger association to HDL concentration than EPA. For both genders, concentration of large LDL particles showed associations to levels of EPA, but stronger to DHA and DPA. High values of EPA/AA seem to be the strongest single biomarker for good CV health in both men and women.publishedVersio

Intensive lifestyle intervention provides rapid reduction of serum fatty acid levels in women with severe obesity without lowering omega-3 to unhealthy levels

Serum fatty acid (FA) levels were monitored in women with severe obesity during intensive lifestyle intervention. At baseline, total FA levels and most individual FAs were elevated compared to a matching cohort of normal and overweight women (healthy controls). After 3 weeks of intensive lifestyle intervention, total level was only 11–12% higher than in the healthy controls and with almost all FAs being significantly lower than at baseline, but with levels of omega-3 being similar to the healthy controls. This is contrary to observations for patients subjected to bariatric surgery where omega-3 levels dropped to levels significantly lower than in the lifestyle patients and healthy controls. During the next 3 weeks of treatment, the FA levels in lifestyle patients were unchanged, while the weight loss continued at almost the same rate as in the first 3 weeks. Multivariate analysis revealed that weight loss and change of serum FA patterns were unrelated outcomes of the intervention for lifestyle patients. For bariatric patients, these processes were associated probably due to reduced dietary input and increased input from the patients’ own fat deposits, causing a higher rate of weight loss and simultaneous reduction of the ratio of serum eicosapentaenoic to arachidonic acid.publishedVersio

Associations of physical activity and sedentary time with lipoprotein subclasses in Norwegian schoolchildren: The Active Smarter Kids (ASK) study

Background and aims: Physical activity is favourably associated with certain markers of lipid metabolism. The relationship of physical activity with lipoprotein particle profiles in children is not known. Here we examine cross-sectional associations between objectively measured physical activity and sedentary time with serum markers of lipoprotein metabolism. Methods: Our cohort included 880 children (49.0% girls, mean age 10.2 years). Physical activity intensity and time spent sedentary were measured objectively using accelerometers. 30 measures of lipoprotein metabolism were quantified using nuclear magnetic resonance spectroscopy. Multiple linear regression models adjusted for age, sex, sexual maturity and socioeconomic status were used to determine associations of physical activity and sedentary time with lipoprotein measures. Additional models were adjusted for adiposity. Isotemporal substitution models quantified theoretical associations of replacing 30 min of sedentary time with 30 min of moderate- to vigorous-intensity physical activity (MVPA). Results: Time spent in MVPA was associated with a favourable lipoprotein profile independent of sedentary time. There were inverse associations with a number of lipoprotein measures, including most apolipoprotein B-containing lipoprotein subclasses and triglyceride measures, the ratio of total to high-density lipoprotein (HDL) cholesterol, and non-HDL cholesterol concentration. There were positive associations with larger HDL subclasses, HDL cholesterol concentration and particle size. Reallocating 30 min of sedentary time to MVPA had broadly similar associations. Sedentary time was only partly and weakly associated with an unfavourable lipoprotein profile. Conclusions: Physical activity of at least moderate-intensity is associated with a favourable lipoprotein profile in schoolchildren, independent of time spent sedentary, adiposity and other confounders.acceptedVersio

Associations of lipoprotein particle profile and objectively measured physical activity and sedentary time in schoolchildren: a prospective cohort study

Background: Our understanding of the mechanisms through which physical activity might benefit lipoprotein metabolism is inadequate. Here we characterise the continuous associations between physical activity of different intensities, sedentary time, and a comprehensive lipoprotein particle profile. Methods: Our cohort included 762 fifth grade (mean [SD] age = 10.0 [0.3] y) Norwegian schoolchildren (49.6% girls) measured on two separate occasions across one school year. We used targeted proton nuclear magnetic resonance (1H NMR) spectroscopy to produce 57 lipoprotein measures from fasted blood serum samples. The children wore accelerometers for seven consecutive days to record time spent in light-, moderate-, and vigorous-intensity physical activity, and sedentary time. We used separate multivariable linear regression models to analyse associations between the device-measured activity variables—modelled both prospectively (baseline value) and as change scores (follow-up minus baseline value)—and each lipoprotein measure at follow-up. Results: Higher baseline levels of moderate-intensity and vigorous-intensity physical activity were associated with a favourable lipoprotein particle profile at follow-up. The strongest associations were with the larger subclasses of triglyceride-rich lipoproteins. Sedentary time was associated with an unfavourable lipoprotein particle profile, the pattern of associations being the inverse of those in the moderate-intensity and vigorous-intensity physical activity analyses. The associations with light-intensity physical activity were more modest; those of the change models were weak. Conclusion: We provide evidence of a prospective association between time spent active or sedentary and lipoprotein metabolism in schoolchildren. Change in activity levels across the school year is of limited influence in our young, healthy cohort.publishedVersio

Pärjäin : tiennäyttäjä kansalaisen hyvinvointipolulla?

Kansalaisen on joskus vaikea löytää eri toimijoiden palveluvalikoimasta niitä palveluita, jotka vastaavat juuri hänen tarpeisiinsa. Tarvitaan uudenlaisia ratkaisumalleja, jotta henkilökohtaisuus, aika‐ ja paikkariippumattomuus, kansalaisten erilaiset kyvyt sekä uuden teknologian tuomat mahdollisuudet voidaan ottaa paremmin huomioon. Tekesrahoitteisessa OmaHyvinvointi‐hankkeessa (OHV) aikaisemmin kehitettyä Pärjäin‐konseptia sovelletaan ja kehitetään edelleen EAKR‐rahoitteisessa Pumppu‐hankkeessa kohti käytännön hyvinvointinavigaattoria, kansalaisen omaksi, arjen hyvinvoinnin tukijaksi. Tässä artikkelissa on tarkoituksena kuvata Laurea‐ammattikorkeakoulussa tehtyjä selvityksiä iäkkäiden ihmisten ITvalmiuksista, palvelutarpeista ja haasteista sekä IT‐pohjaisista interventioista ja Pärjäin‐tyyppisen sovelluksen mahdollisuuksista toimia sydänpotilaan hoitopolun tukena. Tavoitteena on tuottaa tietoa kansalaisen arjen elämää helpottavien palveluiden ja teknologioiden kehittämistyöhön. Kohderyhminä ovat iäkkäät eläköityvät ja sydän‐ ja diabetespotilaat Länsi‐Uudellamaalla ja tutkimusympäristönä Pumppu‐hanke. Pumppu–hanke on ylimaakunnallinen Euroopan Aluekehitysrahaston osittain rahoittama (EAKR) hanke, jossa kehitetään kansalaislähtöisiä, monitoimijaisia hyvinvointipalveluja. Tässä artikkelissa esitellään kolmen erillisen opinnäytetyön tuloksia, joiden aineistot on kerätty kyselytutkimuksena, kirjallisuuskatsauksena sekä fokusgroup‐haastatteluna ja analysoitu kuvailevalla tilastollisella analyysillä sekä sisällönanalyysillä. Tulosten mukaan iäkkäät henkilöt suosivat edelleen paperidokumentteja, vaikka merkkejä asennoitumisen muuttumisesta on nähtävissä nuoremmilla eläköityvillä vastaajilla. Mikäli sähköisiä palveluita käytettäisiin, olisi toivotuin väline tietokone ja tiedonsaantimuoto oma sähköpostitili. Sydänpotilaat kokivat hoitonsa pirstaleiseksi ja tiedonkulun puutteelliseksi. Ajatukset Pärjäin–tyyppisestä navigaattorista arjen apuna olivat myönteisiä niillä, jotka olivat tottuneita tietokoneen käyttöön. Oma osaaminen huoletti erityisesti tietokoneen käyttöön tottumattomia. Kirjallisuuskatsauksessa analyysin mukaan kansalaiset, jotka asuivat etäällä palveluista, kokivat etäkonsultaatiomenetelmien parantavan terveyspalvelujen saatavuutta ja tuottivat myös organisaatioille kustannussäästöjä