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Dive into the research topics where Paula Summanen is active.

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Featured researches published by Paula Summanen.


The Lancet | 2007

Effect of fenofibrate on the need for laser treatment for diabetic retinopathy (FIELD study): a randomised controlled trial

Anthony Keech; Paul Mitchell; Paula Summanen; Justin O'Day; T. M. E. Davis; Moffitt; M.-R. Taskinen; R. J. Simes; Dana Tse; Elizabeth Williamson; A. Merrifield; Leila Laatikainen; Michael d'Emden; Dc Crimet; Rachel O'Connell; Peter G. Colman

BACKGROUND Laser treatment for diabetic retinopathy is often associated with visual field reduction and other ocular side-effects. Our aim was to assess whether long-term lipid-lowering therapy with fenofibrate could reduce the progression of retinopathy and the need for laser treatment in patients with type 2 diabetes mellitus. METHODS The Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study was a multinational randomised trial of 9795 patients aged 50-75 years with type 2 diabetes mellitus. Eligible patients were randomly assigned to receive fenofibrate 200 mg/day (n=4895) or matching placebo (n=4900). At each clinic visit, information concerning laser treatment for diabetic retinopathy-a prespecified tertiary endpoint of the main study-was gathered. Adjudication by ophthalmologists masked to treatment allocation defined instances of laser treatment for macular oedema, proliferative retinopathy, or other eye conditions. In a substudy of 1012 patients, standardised retinal photography was done and photographs graded with Early Treatment Diabetic Retinopathy Study (ETDRS) criteria to determine the cumulative incidence of diabetic retinopathy and its component lesions. Analyses were by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN64783481. FINDINGS Laser treatment was needed more frequently in participants with poorer glycaemic or blood pressure control than in those with good control of these factors, and in those with a greater burden of clinical microvascular disease, but the need for such treatment was not affected by plasma lipid concentrations. The requirement for first laser treatment for all retinopathy was significantly lower in the fenofibrate group than in the placebo group (164 [3.4%] patients on fenofibrate vs 238 [4.9%] on placebo; hazard ratio [HR] 0.69, 95% CI 0.56-0.84; p=0.0002; absolute risk reduction 1.5% [0.7-2.3]). In the ophthalmology substudy, the primary endpoint of 2-step progression of retinopathy grade did not differ significantly between the two groups overall (46 [9.6%] patients on fenofibrate vs 57 [12.3%] on placebo; p=0.19) or in the subset of patients without pre-existing retinopathy (43 [11.4%] vs 43 [11.7%]; p=0.87). By contrast, in patients with pre-existing retinopathy, significantly fewer patients on fenofibrate had a 2-step progression than did those on placebo (three [3.1%] patients vs 14 [14.6%]; p=0.004). An exploratory composite endpoint of 2-step progression of retinopathy grade, macular oedema, or laser treatments was significantly lower in the fenofibrate group than in the placebo group (HR 0.66, 95% CI 0.47-0.94; p=0.022). INTERPRETATION Treatment with fenofibrate in individuals with type 2 diabetes mellitus reduces the need for laser treatment for diabetic retinopathy, although the mechanism of this effect does not seem to be related to plasma concentrations of lipids.


Ophthalmology | 2000

Tumor doubling times in metastatic malignant melanoma of the uvea: Tumor progression before and after treatment

Sebastian Eskelin; Seppo Pyrhönen; Paula Summanen; Marjo Hahka-Kemppinen; Tero Kivelä

OBJECTIVE To obtain estimates of growth rate of metastatic uveal melanoma to infer appropriate follow-up programs and to assess the impact of current chemoimmunotherapy regimens. DESIGN Retrospective case series. PARTICIPANTS Of 70 consecutive patients diagnosed with metastatic uveal melanoma from 1986 through 1998, 37 patients who attended regular follow-up and had measurable metastases were eligible for this study. METHODS Tumor doubling time (DT) was calculated by the Schwartz formula using three presumed sizes of metastasis at last negative follow-up. DT was compared according to tumor characteristics, and time of micrometastasis was estimated. MAIN OUTCOME MEASURES Doubling time of untreated and treated metastases. RESULTS Doubling time of untreated metastases ranged from 34 to 220 days (median, 63 days). Regardless of the presumed size of metastasis at last screening, two thirds of the metastases had a DT between 30 and 80 days. No significant correlation between DT and the observed disease-free interval was detected. Assuming constant growth rate, most metastases had predictably initiated within 5 years before primary treatment. Mean DT during active treatment of metastases in 18 patients who did not show an objective response ranged from 25 to 2619 days (median, 255 days). CONCLUSIONS Based on the estimated growth rates, a rational follow-up interval to detect metastatic uveal melanoma would be 4 to 6 months. Primary uveal melanomas that develop clinically detectable metastasis after conservative therapy may micrometastasize several years before treatment. These estimates are rough and must be confirmed by prospective studies. Current chemoimmunotherapy regimens slow down the growth rate of metastases even if objective response is not obtained.


Diabetologia | 1998

Risk factors for mortality in Type II (non-insulin-dependent) diabetes: evidence of a role for neuropathy and a protective effect of HLA-DR4

Carol Forsblom; T. Sane; Per-Henrik Groop; K. J. Tötterman; Milla Kallio; Carola Saloranta; L. Laasonen; Paula Summanen; Mauri Lepäntalo; Leila Laatikainen; E. Matikainen; A. M. Teppo; Saija Koskimies; Leif Groop

Summary To test the hypothesis that interaction between genetic, immunological, clinical and metabolic risk factors influences the outcome of Type II (non-insulin-dependent) diabetes mellitus, we examined which of the above factors present at baseline were associated with mortality in 134 Type II diabetic patients followed for 9 years. Thirty-eight patients (29 %) died during the follow-up period; the majority of whom (68 %) died from cardiovascular disease. At baseline, the deceased patients had higher HbA1 c values (p = 0.002), higher LDL-triglycerides (p = 0.007), lower HDL-cholesterol (p = 0.007), higher non-esterified fatty acid (NEFA) concentrations (p = 0.014), and higher albumin excretion rate (p < 0.0001) than the patients who survived. In addition, the frequency of HLA-DR4 (21 vs 39 %, p = 0.048) and of parietal cell antibodies (5 vs 14 %, p = 0.016) were decreased in the deceased as compared to the living patients. Patients who died during follow-up also had more retinopathy (42 vs 16 %, p = 0.002), neuropathy (57 vs 23 %, p < 0.001), microalbuminuria (45 vs 6 %, p < 0.0001), coronary heart disease (50 vs 13 %, p < 0.0001), and peripheral vascular disease (27 vs 9 %, p = 0.005) at baseline than patients who survived. In a multiple logistic regression analysis macroangiopathy (p = 0.004), neuropathy (p = 0.007), HbA1 c (p = 0.018) and albumin excretion rate (p = 0.016) were independent risk factors for death. In patients free of cardiovascular disease at baseline, conventional risk factors such as LDL-cholesterol (p = 0.005) and age (p = 0.003) were associated with subsequent development of cardiovascular disease. In conclusion, in addition to coexisting macroangiopathy, increased albumin excretion rate, poor glycaemic control and neuropathy are risk factors for cardiovascular mortality in patients with Type II diabetes. The presence of HLA-DR4 and signs of autoimmunity may be associated with decreased risk of cardiovascular disease. [Diabetologia (1998) 41: 1253–1262]


Diabetes | 2008

Heritability of proliferative diabetic retinopathy

Kustaa Hietala; Carol Forsblom; Paula Summanen; Per-Henrik Groop

OBJECTIVE—Diabetic nephropathy clusters in families, suggesting that genetic factors play a role in its pathogenesis. We investigated whether similar clustering exists for proliferative retinopathy in families with two or more siblings with type 1 diabetes. RESEARCH DESIGN AND METHODS—The FinnDiane Study has characterized 20% (4,800 patients) of adults with type 1 diabetes in Finland. In 188 families, there were at least two siblings with type 1 diabetes. Ophthalmic records were obtained for 369 of 396 (93%) and fundus photographs for 251 of 369 (68%) patients. Retinopathy was graded based on photographs and/or repeated ophthalmic examinations using the Early Treatment of Diabetic Retinopathy grading scale. RESULTS—Mean age at onset of diabetes was 14.3 ± 10.2 years, and mean duration was 25.9 ± 11.8 years. Proliferative retinopathy was found in 115 of 369 patients (31%). The familial risk of proliferative retinopathy was estimated in 168 of 188 sibships, adjusted for A1C, duration, and mean blood pressure. Proliferative retinopathy in the probands (48 of 168) was associated with an increased risk (odds ratio 2.76 [95% CI 1.25- 6.11], P = 0.01) of proliferative retinopathy in the siblings of probands (61 of 182). The heritability of proliferative retinopathy was h2 = 0.52 ± 0.31 (P < 0.05). CONCLUSIONS—We found a familial clustering of proliferative retinopathy in patients with type 1 diabetes. The observation cannot be accounted for by conventional risk factors, suggesting a genetic component in the pathogenesis of proliferative retinopathy in type 1 diabetes.


British Journal of Ophthalmology | 1996

Radiation related complications after ruthenium plaque radiotherapy of uveal melanoma.

Paula Summanen; Ilkka Immonen; Tero Kivelä; Petri Tommila; Jorma Heikkonen; Ahti Tarkkanen

AIMS/BACKGROUND: To analyse radiation related complications and secondary enucleation after irradiation of malignant uveal melanoma with ruthenium-106 plaques. METHODS: A series of 100 consecutive eyes irradiated in 1981-91 was analysed using the life table method and the Cox proportional hazards model. The median apical and scleral tumour dose was 100 Gy (range 15-200 Gy) and 1000 Gy (range 200-1200 Gy), respectively. The median follow up time was 2.8 and 2.0 years (range 1 month to 10 years) for anterior and posterior segment complications, respectively. RESULTS: The 3 and 5 year probabilities of being without radiation cataract were 73% and 63%, without neovascular glaucoma 91% and 81%, without vitreous haemorrhage 83% and 74%, without radiation maculopathy 85% and 70%, and without radiation optic neuropathy 90% and 88%, respectively. The risk of radiation cataract was highest with large tumour size (T1 + T2 v T3, p = 0.0027; height < or = 5 v > 5 mm, p = 0.029; largest basal diameter (LBD) < or = 15 v > 15 mm, p < 0.0001) and location of anterior tumour margin anterior v posterior to the equator (p = 0.0003); the risk of neovascular glaucoma with large size (T1 + T2 v T3, p = 0.039; LBD < or = 15 mm v 15 mm, p = 0.021); and the risk of maculopathy and optic neuropathy with proximity of the posterior tumour margin to the fovea and the optic disc (< or = 1.5 v > 1.5 mm; p = 0.030 and p = 0.0004, respectively). In Coxs multivariate analysis the strongest risk indicator for radiation cataract (RR 1.5, 95% CI 1.4-1.6) and vitreous haemorrhage (RR 1.6, 95% CI 1.4-1.8) was the height of the tumour; for neovascular glaucoma the TNM class (RR 6.2, 95% CI 2.7-13.8); for radiation maculopathy location of posterior tumour margin within 2 mm from the fovea (RR 3.4, 95% CI 2.0-6.0); and for radiation optic neuropathy location of tumour margin within 1 DD of the optic disc (RR 6.1, 95% CI 3.0-12.4). The 3 and 5 year probabilities of avoiding enucleation were 92% and 85%, respectively. Ten eyes were enucleated--six because of recurrent tumour growth, three because of treatment complications, and one because of mistakenly suspected extraocular growth. CONCLUSION: The results suggest that the frequency of radiation related complications after ruthenium brachytherapy of uveal melanoma is acceptable, in particular as regard irradiation of small and medium sized tumours for which ruthenium therapy generally is recommended.


Ophthalmology | 2003

Iodine brachytherapy as an alternative to enucleation for large uveal melanomas.

Ilkka Puusaari; Jorma Heikkonen; Paula Summanen; Ahti Tarkkanen; Tero Kivelä

PURPOSE To evaluate the safety and efficacy of iodine 125 plaque brachytherapy (IBT) for large uveal melanomas. DESIGN Retrospective, nonrandomized comparative trial (historical control). PARTICIPANTS One hundred twenty-one consecutive patients with a large uveal melanoma according to the Collaborative Ocular Melanoma Study (COMS) criteria who attended a national ocular oncology service. METHODS Ninety-seven patients (80%) underwent primary IBT (mean dose to tumor apex, 87 Gy) with noncollimated 20- to 25-mm plaques. Assessment of metastatic disease at death and visual outcome followed COMS guidelines. Time to low vision (20/70 or worse) and blindness (loss of 20/400 vision) in the study eye were modeled by Cox proportional hazards regression, based on both single- and repeated-failure data sets. Person-years of retained vision were calculated. MAIN OUTCOME MEASURES All-cause and melanoma-specific survival, local and distant recurrence, and preservation of vision and cosmesis. RESULTS Median tumor height was 10.7 mm (range, 4.5-16.8 mm), and largest basal tumor diameter was 16.1 mm (range, 7.3-25.0 mm). The Kaplan-Meier estimate for all-cause and melanoma-specific survival was 62% (95% confidence interval [CI], 49%-72%) and 65% (95% CI, 52%-75%) at 5 years. The corresponding estimate for local tumor recurrence was 6% (95% CI, 2%-14%) and for major cosmetic abnormality was 38% (95% CI, 26%-52%). The median visual acuity in the study eye was 20/100 at baseline and 20/1600 at 2 years after treatment. The Kaplan-Meier estimate for avoiding low vision and blindness was 11% (95% CI, 4%-24%) and 26% (95% CI, 16%-37%) at 2 years, respectively. Tumor height and location entirely posterior to the ora serrata were the most robust predictors of visual loss. In this series, 49 person-years without low vision (median, 0.6 years; range, 0.04-8.2 years) and 111 person-years without blindness (median, 1.0 years; range, 0.03-8.6 years) in the treated eye were conserved. CONCLUSIONS Iodine 125 plaque brachytherapy seems to be a safe and effective alternative to enucleation with regard to survival and local tumor control. It provides a fair chance of preserving the eye with acceptable cosmesis and a reasonable chance of conserving useful vision for 1 to 2 years.


Ophthalmology | 1998

Ophthalmologic findings in long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency caused by the G1528C mutation : A new type of hereditary metabolic chorioretinopathy

Tiina Tyni; Tero Kivelä; Marjatta Lappi; Paula Summanen; Eeva Nikoskelainen; Helena Pihko

OBJECTIVE The purpose of the study was to determine the nature and course of ophthalmic abnormalities in long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency, a recently discovered disorder of mitochondrial fatty acid beta-oxidation. STUDY DESIGN The study design was a cohort (case series). PARTICIPANTS A retrospective review of the records of 15 children who had died during their first 2 years was performed. Also performed were a longitudinal reanalysis and cross-sectional clinical examination of four long-term survivors aged 5 to 31 years. MAIN OUTCOME MEASURES Visual acuity, refraction, visual fields, ophthalmoscopy, fluorescein angiography, biometry, corneal topography, electroretinography (ERG), visual-evoked potentials (VEPs), color vision, and dark adaptation were measured. RESULTS In seven children, ophthalmoscopic findings were within normal limits at 3 days to 13 months of age (median, 4.8 months). In 11 children, a granular retinal pigment epithelium (RPE), with or without pigment clumping in the macula, was seen at 4 months to 5 years of age (median, 9 months). Two long-term survivors, 16 and 31 years of age, eventually had circumscribed atrophy of the choroid, RPE, and retina, which coincided with a posterior staphyloma type 1. They had progressive axial myopia starting at 6 and 12 years of age and later paracentral scotomas leading to poor central vision. They suffered from early difficulty with mesopic vision, glare, and a severe generalized color vision deficiency that started as a tritanomaly. A third survivor was mildly myopic at 5 years of age. All four surviving patients had visually insignificant, flake-like supranuclear opacities in the lens. The ERG initially was normal but deteriorated during the first decade and later was unrecordable. The VEP responses remained fairly normal. Initially, angiography showed no blockade of the choroidal fluorescence because of the thin RPE. Filling of choroidal vessels was delayed, and the choriocapillaris and, later, larger choroidal vessels in the posterior pole became nonperfused. CONCLUSIONS In LCHAD deficiency, the fundus is normal at birth (stage 1). Soon, however, pigment dispersion occurs in the RPE (stage 2), followed by circumscribed chorioretinal atrophy, occlusion of choroidal vessels, and deterioration of central vision, often with relative sparing of the peripheral fundus (stage 3). Finally, posterior staphylomas and central scotomas may develop (stage 4). Developmental cataract, progressive myopia, and deterioration of visual fields and color vision are new findings in LCHAD deficiency. The chorioretinopathy and abnormal ERG precede the development of myopia and posterior staphyloma, which, in turn, coincide with the loss of macular vision. The authors postulate that the RPE or choriocapillaris is primarily affected. Awareness of the characteristic ocular features is important because of an opportunity for dietary treatment, genetic counseling, and prenatal diagnosis.


Journal of Cerebral Blood Flow and Metabolism | 2004

Brain Metabolic Alterations in Patients With Type 1 Diabetes-Hyperglycemia-Induced Injury

Sari Mäkimattila; Kirsi Malmberg-Céder; Anna-Maija Häkkinen; Kim Vuori; Oili Salonen; Paula Summanen; Hannele Yki-Järvinen; Markku Kaste; Sami Heikkinen; Nina Lundbom; Risto O. Roine

Microangiopathic end-organ injury is common in type 1 diabetes. However, the pathophysiology of diabetic encephalopathy is poorly understood. The authors studied 10 normotensive patients with type 1 diabetes with retinopathy, autonomic neuropathy, but without nephropathy, and 10 healthy subjects. Proton magnetic resonance spectroscopy was performed at 1.5 T in the frontal cortex, thalamus, and posterior frontal white matter. There was no change in N-acetyl–containing compounds (NA), but choline-containing compounds (Cho) were increased in the white matter and in the thalamus; myo-inositol was increased in the white matter, glucose excess was found in all brain, and water intensity was increased in the cortical voxel in the patients. Calculated lifetime glycemic exposure correlated inversely with Cho and NA in white matter and with Cho in thalamus. Concentrations of soluble intercellular adhesion molecules and vascular cell adhesion molecules were increased in the patients. In conclusion, in patients with type 1 diabetes, the increase in adhesion molecules and an association between altered brain metabolites and glycemic exposure suggest the presence of a vascularly mediated, progressive metabolic disturbance in the brain.


Acta Neurochirurgica | 1999

Long-Term Prognosis of Haemangioblastoma of the CNS: Impact of von Hippel-Lindau Disease

Mika Niemelä; S. Lemeta; Paula Summanen; Tom Böhling; Markku Sainio; Juha Kere; K. Poussa; R. Sankila; Hannu Haapasalo; Helena Kääriäinen; E. Pukkala; Juha Jääskeläinen

Summary¶ The aim was to assess the frequency of von Hippel-Lindau disease (VHL) and the long-term prognosis of VHL and non-VHL patients among 110 consecutive patients with haemangioblastoma (HB) of the CNS treated between 1953 and 1993 at one neurosurgical unit. To reveal VHL manifestations we performed a detailed clinical and radiological examination (neuraxis and abdomen) (61/110), VHL-gene mutation analysis (40/110), and collection of all available clinical, imaging, operative and autopsy data from the hospitals involved. All patients were followed-up with a median of 14 years (excluding 14 operative deaths), and no patient was lost to follow-up. Altogether 49 patients died during the follow-up. In the 14 VHL patients (13%), HB(s) of the CNS were detected at a median age of 33 years, retinal HB(s) at 39 years, and renal cell carcinoma (RCC) at 43 years. The frequency of VHL in patients operated on for HB(s) was 29% before the age of 25 years, 19% between 25 and 45 years, and only 2% after 45 years. HB patients not meeting the VHL criteria had internal organ cysts in 14%. One non-VHL patient (4%) had two adjacent HBs in the same cyst wall. The growth rates of non-VHL and VHL-related HBs were similar as indicated by the median time to recurrence and the proliferation indices (MIB-1). Recurrence of the HB in patients whose primary operation was considered radical developed in four of the 10 VHL patients at a median of 19 years, and in nine of the 74 non-VHL patients at a median of 11 years. The median length of life of all VHL and non-VHL patients was 46 and 63 years, respectively. In VHL, RCC and HBs were equal causes of death.


Circulation | 1997

Hyperreactivity to Nitrovasodilators in Forearm Vasculature Is Related to Autonomic Dysfunction in Insulin-Dependent Diabetes Mellitus

Sari Ma¨kimattila; Matti Ma¨ntysaari; Per-Henrik Groop; Paula Summanen; Antti Virkama¨ki; Anna Schlenzka; Johan Fagerudd; Hannele Yki-Ja¨rvinen

BACKGROUND The link between diabetes and vascular disease is poorly understood. Data regarding endothelial function in vivo in patients with insulin-dependent diabetes mellitus (IDDM) have been inconsistent with in vitro studies demonstrating hyperglycemia-induced impairments in endothelium-dependent vasodilation. METHODS AND RESULTS We determined whether alterations in neural control of the vascular tone might contribute to blood flow responses to intrabrachial infusions of acetylcholine (ACh), sodium nitroprusside (SNP), and L-N-monomethyl-arginine (L-NMMA) in 22 men with IDDM (12 with normoalbuminuria. HbA1c = 8.6 +/- 0.3%; 10 with macroalbuminuria, HbA1c = 8.6 +/- 0.3%) and 11 matched normal men. Autonomic function was assessed from reflex vasoconstriction to cold, the blood pressure response to standing and hand grip, and heart rate variation, including spectral analysis, during controlled breathing, and the Valsalva maneuver. IDDM with macroalbuminuria exhibited hyperresponsiveness to both ACh and SNP compared with the patients with normoalbuminuria or normal subjects. Reflex sympathetic vasoconstriction to cold was severely impaired in the IDDM patients with macroalbuminuria (-19 +/- 6%) compared with normoalbuminuric patients (-39 +/- 5%, P < .05) and normal subjects (-54 +/- 7%, P < .001). The macroalbuminuric patients also had evidence of autonomic dysfunction during controlled and deep breathing tests and during the Valsalva maneuver. Within the group of IDDM patients, neither the urinary albumin excretion rate nor other parameters such as HbA1c or serum cholesterol correlated with forearm blood flow during the vasoactive drug infusions. There were, however, significant inverse correlations between several measures of both sympathetic and parasympathetic autonomic functions and vascular hyperresponsiveness to SNP and ACh. For example, the Valsalva ratio was inversely correlated with the increase in blood flow in response to infusion of 3 (r = -.74, P < .001) and 10 (r = -.73, P < .001) micrograms/min SNP and 7.5 (r = -.73, P < .001) and 15 (r = -.75, P < .001) micrograms/min ACh. CONCLUSIONS These data are consistent with idea that altered neurotransmission is an important determinant of vascular reactivity of diabetic blood vessels to nitrovasodilators in vivo.

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Carol Forsblom

Helsinki University Central Hospital

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Janne P. Kytö

Helsinki University Central Hospital

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Petri Tommila

Helsinki University Central Hospital

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